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The Doctor Will See You Now: Diving Fitness and

Medical Examinations

                                                                                          By Alex Brylske

I'm sure that there are places where I’m more ill at ease than in a doctor’s office, but I can’t really think of one. This isn’t to say that I don’t take my health care seriously. My doc is an affable and competent person whom, like it or not, I visit on a fairly regular basis. Over the past several years I’ve been poked, probed, palpated, stuck, irradiated and imaged in every way imaginable, and some that aren’t so. Heck, I even get my teeth cleaned twice a year. However, I’m not one who runs out to the doctor for a hangnail or at the first sign of a cold. In fact, as testament to my abhorrence to anything medical, there have only been two occasions in my entire adult life when I visited a doctor for something other than preventive care.

My fear and loathing of medicos goes back to my childhood. I had had two operations by the time I was 6 years old, and that much hospital experience for one so young definitely has an effect. Even as a teenager, as much as I dreamed of becoming a diver, I was initially reluctant to get certified when I learned that it would require a medical examination.

Of course, knowing one’s level of fitness is essential to safe diving because, regardless of how easy it has become, surviving underwater subjects our bodies to some pretty stressful and unforgiving situations. But what exactly constitutes “fitness to dive,” and how can we assess that? Does determining our fitness always require the insight of a trained medical professional? These questions have been debated since the beginning of recreational diving and, as in most fields, opinions and practices have changed over the years. Even today, polices on prequalification medical exams and diving fitness are not universal.

The What and Why of ‘Fitness’

In scuba diving, when it comes to assessing fitness, times have certainly changed. Years ago, many were reluctant to even consider diving because they thought it was deep, dark and dangerous. Today, it’s just the opposite. Many are lulled into diving because they view it as simple, safe and easy. Indeed, diving takes place in a relatively weightless environment, which may make it seem effortless, but it does require a degree of both health and stamina.

In determining what fitness means to you, understand that there’s no single answer; it means different things to different people. The first issue to consider in evaluating your fitness level is where and what type of diving you plan to do. Obviously, enjoying a shallow reef in the Florida Keys on a still summer morning is far less demanding than braving 8-foot seas to dive the wrecks off the New Jersey coast. Although this may seem obvious, it’s amazing how many folks will assume that their Florida Keys fitness is all they need when they one day decide to dive New Jersey or California. Your well-being demands that you be honest about what you want from the diving experience, and make sure that you don’t exceed the conditions on which you’ve based your fitness decision.

Still, even if you do decide that you’re only interested in relatively “easy” conditions and environments, things don’t always go as planned. Even the best conditions can change rapidly, and it’s these unforeseen circumstances that cause a lot of accidents. So, whatever you expect, assume that once in a while, at least, conditions will be worse; perhaps much worse. This means that you must possess not only the level of fitness required for what you normally encounter, but a “reserve,” just in case. Granted, assessing, acquiring and maintaining an appropriate level of fitness may not be easy, but never forget that Murphy’s Law is always right around the corner ready to bite you on the backside when you least expect it.

Whether you expect it or not, on any dive you may encounter long surface swimming, have to contend with strong, changing currents or just deal with being at the surface in conditions akin to a washing machine during the rinse cycle. All require more fitness than walking from your easy chair to the fridge. Unanticipated and strenuous physical tasks are part of the diving experience in any environment; therefore you must not have any health conditions, or take any medications, that may impede your performance.

Assessing your fitness also isn’t a one-time event. When I started diving as a young teenager, there were few physical tasks a diver might encounter that I couldn’t handle. But to assume that’s still the case more than three decades later is a recipe for disaster. So, the next time you’re filling out your logbook, take a few minutes to ask yourself a few simple questions: Did I encounter conditions that were close to or beyond my physical capabilities? How likely is it that these conditions may occur again? Do I need to reconsider my “comfort envelope” or try to improve my fitness? The answers require a great deal of self-honesty, but the exercise may be the best thing you’ll ever do for your health and well-being.

Finding a clear method to assess and quantify your level of fitness isn’t always easy, but there are some basics you can keep in mind. First, if you can’t walk around the block without a rest, or if you’ve never even tried, diving at any level probably isn’t something you should try (or continue). At least, not until you’ve improved your conditioning. A very minimal guideline for fitness is the ability to walk a mile (1.6 km) within 12 minutes. If you can’t do this, you should plan to exercise for at least 20 minutes four or five time per week, but only after you’ve gotten the approval of your doctor. And if possible, add swimming with fins to your routine. A useful measure that I’ve always given my own students, based on years of teaching experience, is this: No one should consider themselves prepared for a certification course who cannot swim at their own pace, using a mask and fins, at least 200 yards (182 m) without stopping and/or becoming exhausted.

Restrictions and Red Flags

Aside from physical fitness, divers and would-be divers must also consider how any existing medical conditions can affect their health and safety. Surviving in an environment that’s 800 times denser than the atmosphere can present problems that might never arise while sitting in your living room, or even engaging in moderate physical activity on terra firma.

First, let’s consider temporary conditions such as colds, flu, injury or even pregnancy. All should be considered reasons to curtail diving until the effects have passed. Colds, flu or allergy attacks cause swelling or blockage in the sinuses and eustachian tubes, which means pressure equalization will be difficult or impossible. Injuries can leave you with restricted strength, stamina or mobility, and can even put you at a greater risk of decompression sickness due to alterations or restrictions in blood flow. Furthermore, when diving with an injury, the accompanying pain could mask symptoms of decompression sickness. So it’s best to postpone diving until you’re fully healed. Lastly, diving while you are or could be pregnant is considered a no-no for one simple reason: We just don’t know enough about its effect on the developing fetus, so why take the chance? Can any hour spent underwater be worth the risk to a child’s life or quality of life?

It should be obvious that you must take into account the effect of any medications. This goes for both prescribed and over-the-counter (OTC) meds. Frankly, most medications have no effect on diving, but some definitely do. They may cause drowsiness or fatigue, which may make you more susceptible to nitrogen narcosis, or impede your thinking at just the time thinking is most critical. Other medications, as well as illicit drugs, can affect heart rate even in those without heart problems. Clearly, if you plan to dive, it’s especially important to read the warning labels before using any drugs. And it’s just downright stupid to dive while taking any recreational drugs.

Another concern that’s foreign to any landlubber taking meds is whether and how the increased pressure at depth can affect any drug. There is always a possibility of such an unexpected reaction to medications, and some drugs are noted particularly for pressure-induced side effects. But the problem is that these reactions can vary from diver to diver, and even from day to day. So, the first step in preventing a dangerous situation is knowing well in advance what side effects any medication has on you before using it while diving. It isn’t smart to pop a pill for the first time just as you’re about to enter the water. This is true even of common OTC drugs like cold and allergy or seasickness medications.

The effect of diving on prescription medication can be a very complex issue, and requires a knowledgeable doctor’s advice. Regardless, always remind your doctor that you’re a diver when he or she prescribes a med. And, if your doc isn’t up on how diving can affect your condition or medications, you should be prepared to provide some resources. (See the sidebar “Educating Your Doctor” on Page 34.)

Some medical conditions aren’t temporary, and these can have major consequences for divers. Two of the more common concerns are asthma and diabetes. Both are becoming epidemic in many regions of the world, including North America, the Caribbean, and the islands of the South Pacific; and many believe that this is the result of lifestyle and the degrading quality of our environment. This is a serious problem for all segments of society, but it poses additional problems for the diving community. For decades there has been much debate about whether to allow those with either condition to dive; and at one time the answer was quite simple: no. But many have questioned such a ban on diving, and today, after careful medication evaluation, some asthmatics are permitted to dive.

Diabetes, as well, is a chronic condition that’s been recently reconsidered by diving medical experts. Today, rather than a blanket disqualification, divers and diving candidates with diabetes are evaluated on a case-by-case basis with an appropriate medical specialist. A similar situation exists for one of the most common disorders in almost every developed society: cardiovascular disease. (For more information, see “The Heart of the Matter,” Dive Training, April 2006.) Research and debate continue regarding both asthma and diabetes, and it’s likely more issues and findings will appear.

This Will Only Hurt a Little

Whether you’re a diver or not, the cornerstone of good health is a regular physical exam. Opinions on how often this should happen seem to vary; and to be perfectly honest, after graduating from college I didn’t set foot in a doctor’s office for almost 20 years. But that all changed when I hit the big 4-0, a milestone no one should ignore. Since then I’ve had regular annual checkups, along with the associated diagnostic, age-appropriate tests involving treadmills, CAT scans, endoscopes, rubber gloves and assorted other accouterments of medical technology.

The issue of physical examinations for divers has undergone quite an evolution. Even today, policy varies from country to country. As I mentioned, when I got certified, everyone was required to first secure medical approval from a physician before being accepted into a class. But in North America, that hasn’t been the case for a long time. As many of you no doubt know from your experience, some of you had to have physical exams, while others didn’t.

North American-based diver training organizations require that all candidates for instruction complete the Recreational Scuba Training Council’s “Medical History Statement and Questionnaire.” (A copy of the form can be downloaded from many sources; just type in the search term “RSTC medical form.”) As the form explains, its purpose is to find out if a perspective diving student should be examined by a doctor before participating in training. A “yes” response to any question doesn’t necessarily disqualify someone from diving, but it does indicate that there could be a pre-existing condition that may affect safety. Therefore, the candidate must seek the advice of a physician before engaging in diving activities.

Some believe that this approach is inadequate, contending that everyone new to diving should first have medical clearance from a physician. In fact, some countries such as Australia require this. But is this additional expense and inconvenience really warranted? Some who have studied the matter don’t think so. For instance, the UK Sport Diving Medical Committee found that examination by a physician was largely unhelpful in identifying divers with significant medical conditions, and concluded that a health questionnaire, like the current medical history form, is perfectly sufficient. A similar result came from a study six years ago published in the British Journal of Sports Medicine.

However, this selective nature of medical exams does not apply to some divers. All commercial divers, including professionals such as divemasters, dive control specialists, assistant instructors and instructors, are required to have full medical clearance before they’re accepted into training. Scientific divers, including most divers in university programs and those working under the guidelines of the American Academy of Underwater Sciences (AAUS), also require full medical evaluation before training, and while active in such programs.

For recreational divers, the current medical standard has been in effect for almost two decades. The questionnaire was developed by the Undersea and Hyperbaric Medical Society (UHMS) and Divers Alert Network (DAN). (More information about the form is contained in “Assessing Your Medical Fitness to Dive” on Page 36.)

In the end, however, the final arbiter of who can enter a diving course, for medical reasons or otherwise, is that of the instructor. In fact, based solely on his or her judgment, an instructor may require anyone to secure medical approval from a physician, even if the candidate has indicated no affirmative answers on the questionnaire.

We all like to think the best of ourselves. And often our image doesn’t reflect reality. Usually, this has little potential to do harm to anything but our ego. But fitness for diving is a different matter. When it comes to fitness, lying to yourself or others can put both you and your buddy at serious risk. Remember, no diver ever thought that they weren’t coming back from their dive.

Educating Your Doctor

As we all know doctors are very busy people. Their medical school training is intense, and with continuing advances in medical research, they have to know more and more. So, it’s no surprise that a subject like diving medicine doesn’t receive much, if any attention, in either medical school or afterward. In fact, if a doctor doesn’t take up diving personally, he may know less about diving medicine than a knowledgeable scuba instructor. This isn’t intended as a slam. It’s just that, in the scheme of things, scuba diving isn’t a very common activity. So, most doctors only rarely deal with divers and would-be divers. As a result, when it comes time for a diving medical exam, you may find yourself in the delicate situation of having to educate your doctor.

But the situation isn’t as daunting as it may sound. The RSTC “Diving Medical Statement and Questionnaire” contains a section designed just for this purpose: “Guidelines for Recreational Scuba Diver’s Physical Examination.” It includes three pages of detailed instructions with 16 medical references. So, when you show up to your doc’s office, be sure that you take a copy of the entire six-page form, not just the part he or she has to sign.

The guidelines discuss areas of concern for divers, and what to look for in a medical assessment. Temporary, relative and severe risk conditions are listed for the neurological, pulmonary, gastrointestinal, orthopedic, hematological, metabolic/endocrinological and otolaryngological systems. There’s also a segment on behavioral health. At a minimum, the examination should include these points. The list of conditions is not all-inclusive, but contains the most commonly encountered medical problems.

The guidelines define “temporary risks” as those that are responsive to treatment, allowing the student to dive safely after they have been resolved. “Relative risks” refer to conditions that exist but, in the judgment of the physician, are not contraindicated for diving. Finally, “severe risk” implies that an individual is believed to be at substantially elevated risk of decompression sickness, pulmonary or otic (ear) barotrauma or altered consciousness with subsequent drowning, compared with the general population. In these cases, as the guidelines state, “The consultants involved in drafting this document would generally discourage a student with such medical problems from diving.”

The guidelines conclude by informing physicians that medical professionals of the Divers Alert Network (DAN) associated with Duke University Health System are available for consultation. If you find that your doc would like even more insights, here are some additional references:

“Medical Examination of Sport Scuba Divers,” 3rd Edition, A.A. Bove, M.D., Ph.D (ed.), Best Publishing Company, P.O. Box 30100, Flagstaff, AZ 86003-0100.

“The Physician’s Guide to Diving Medicine,” C.W. Shilling, C.B. Carlston and R.A. Mathias, Plenum Press, New York, New York (Available through the Undersea and Hyperbaric Medical Association, Bethesda, Maryland)

Assessing Your Medical Fitness to Dive

The “Diving Medical Statement and Questionnaire” has been produced under the auspices of the Recreational Scuba Training Council and endorsed by the Undersea and Hyperbaric Medical Society (UHMS), Divers Alert Network (DAN) and more than two dozen of North America’s top diving medical specialists. To assess whether an individual should have medical clearance to enroll in a scuba course, here are the areas it addresses:

First, the questionnaire addresses those over 45 years of age. For this group, a positive response to smoking, high cholesterol, family history of heart attack or stroke, high blood pressure, diabetes (even if controlled by diet alone), or if you are receiving medical care means a trip to the doctor’s office.

It then goes on to ask all applicants if they have or have ever had any of several medical conditions, listed below; and if they take any prescribed medications for anything other than malaria prophylaxis or birth control. Female diving candidates are asked whether they are, could be or are attempting to become pregnant.

Again, an affirmative response to any of these questions or conditions, and a doctor’s approval is required for continuing with your wishes to become a certified diver.

§                             Asthma, or wheezing with breathing, or wheezing with exercise.

§                             Frequent or severe attacks of hay fever or allergy.

§                             Frequent colds, sinusitis or bronchitis.

§                             Any form of lung disease.

§                             Pneumothorax (collapsed lung).

§                             Other chest disease or chest surgery.

§                             Behavioral health, mental or psychological problems (panic attack, fear of closed or open spaces).

§                             Epilepsy, seizures, convulsions or take medications to prevent them.

§                             Recurring complicated migraine headaches or take medications to prevent them.

§                             Blackouts or fainting (full/partial loss of consciousness).

• Dysentery or dehydration requiring medical intervention.
• Any dive accidents or decompression sickness.
• Inability to perform moderate exercise (i.e., walk 1 mile [1.6 km] within 12 minutes).
• Head injury with loss of consciousness in the past five years.
• Recurrent back problems.
• Back or spinal surgery.
• Diabetes.
• Back, arm or leg problems following surgery, injury or fracture.
• High blood pressure or take medicine to control blood pressure.
• Heart disease.
• Heart attack.
• Angina, heart surgery or blood vessel surgery.
• Sinus surgery.
• Ear disease or surgery, hearing loss or problems with balance.
• Recurrent ear problems.
• Bleeding or other blood disorders.
• Hernia.
• Ulcers or ulcer surgery.
• A colostomy or ileostomy.
• Recreational drug use or treatment for, or alcoholism in the past five years.
  

 A Note from DAN

As of 1/1/20 the Guardian policy is no longer offered to divers age 70 and older.

Preferred and master plans are still available.

 

Health for Diving: A Primer on Diabetes

 

By Robert N. Rossier      Dive Training Magazine

https://dtmag.com/thelibrary/health-diving-diabetes/

Health for Diving: A Primer on Diabetes

We all know there are medical factors that can prevent people from diving. Epilepsy, various heart conditions, loss of consciousness, pneumothorax, some chronic diseases and even some forms of anxiety can spell trouble that may be incompatible with diving. But over the years, the list of contraindications has narrowed, allowing more to enjoy exploration of the underwater world.

One condition that has prevented some people from becoming divers is diabetes. Diabetes affects the body’s ability to produce or respond to insulin — a hormone controlling the metabolism of carbohydrates. The result is abnormal carbohydrate metabolism leading to elevated glucose levels in the blood and urine.

While this might sound innocuous, the long-term effects of diabetes are dead serious. Diabetes takes more lives than AIDS (acquired immunodeficiency syndrome) and breast cancer combined, claiming one American life every three minutes. Diabetes is a leading cause of blindness, kidney failure, amputations, heart failure and stroke. What’s more, the incidence of diabetes is growing. According to diabetesresearch.org, the number of reported cases of people living with diabetes has jumped nearly 50 percent in the past decade and it now affects more than 29 million Americans. On a global scale, diabetes afflicts more than 380 million people, and the World Health Organization estimates that by 2030, the number of people living with diabetes will more than double. Clearly, diabetes is a growing health risk and one that could affect our ability to dive safely. But, at least for some, the door has been opened for scuba diving with diabetes — that is, if the proper conditions are met and the proper protocols are followed.

Defining Diabetes

Diabetes is categorized into two primary types, referred to as Type 1 and Type 2. In those with Type 1 diabetes, the pancreas does not produce insulin or it produces insufficient insulin to meet the body’s needs. Individuals with Type 1 diabetes must receive insulin injections regularly in order to metabolize blood glucose (blood sugar). In the more common Type 2 diabetes, the body may not produce enough insulin or the insulin does not trigger the cells to allow proper metabolism of glucose.

Type 1 and Type 2 diabetes are the most common forms of the disease but other forms exist. Many individuals are also diagnosed with pre-diabetes, a condition in which blood sugar is high but not significantly enough to warrant treatment. Unless changes are made to diet and exercise, those with pre-diabetes are likely to join the ranks of individuals diagnosed with diabetes.

Physiology of Diabetes

To understand the effects of diabetes, we need to have an understanding of some basic human biology. In a normally functioning body, a number of metabolic reactions occur in response to eating. First, the digestion process in the stomach breaks the food down into glucose (a form of sugar), which enters the blood stream and is transported to cells throughout the body. The hormone insulin is secreted by the pancreas, which triggers the cells to allow glucose to enter. Through a process called glycolysis, the glucose is broken down in the production of a molecule called ATP (adenosine triphosphate), which is the source of energy in the cell. Also in response to eating, the cells also synthesize and story fatty acids and proteins. These are all critical functions for a normal, healthy body.

For the person with diabetes, this process simply does not work properly. Type I diabetes is actually an autoimmune condition. The immune system destroys the beta cells in the pancreas, which are responsible for the production of insulin. And without that insulin, glucose does not enter the cells and they run out of energy.

For Type I diabetes, those affected must receive injections of insulin at the appropriate times to control blood glucose levels and allow cells to receive the needed glucose. Eating the right foods at the right time can also help control blood sugar by controlling how much glucose is produced through digestion. Other factors including exercise, stress and general health also affect the body’s need for insulin, so getting the correct timing and dosage for insulin injections can be a challenge.

In Type 2 diabetes, the pancreas has a deficiency of beta cells that create insulin, making it unable to supply enough insulin to the body. In addition, insulin receptors at the cellular level may not respond properly to insulin, limiting the amount of glucose entering the cells and allowing blood glucose to remain elevated. Controlling diet is also important for those with Type 2 diabetes to prevent spikes in blood glucose. Medications are available to help maintain an appropriate low level of blood glucose. For some, additional medications may be available to increase insulin production by the pancreas.

A Balancing Act

The factors that determine blood glucose levels fluctuate greatly throughout every day, so for a Type 1 diabetic, determining the proper dose of insulin to take can be a complex and sometimes delicate balancing act. Too much insulin means the body consumes too much glucose, which can drive blood glucose to a dangerously low level. This low blood glucose condition, referred to as hypoglycemia, can sometimes be fatal if prompt corrective action is not taken.

With too little insulin, blood glucose can soar to dangerous levels while at the cellular level the body is starved of energy. This condition is referred to as hyperglycemia and it poses a risk of long-term complications.

The goal, then, is to take the necessary steps to maintain a relatively constant blood glucose level as we eat and perform various activities throughout the day. One way that those challenged with diabetes can help avoid the spikes that can come, is to pay attention to what they eat and when they eat it. If such an individual doesn’t eat at the right time or eats too much of the wrong thing (or right thing) at the wrong time, the system can easily be thrown out of balance. In addition to proper eating and dietary habits, other natural remedies have also been widely used to help keep blood sugar levels in check. For example, Gymnema sylvestre is an herb used for centuries in India to help control blood glucose by stimulating pancreatic function.

Contributing Factors

Numerous factors affect blood glucose levels, as well as overall health for all of us. These are of particular importance to those with pre-diabetes or diabetes. One factor that contributes to elevated blood glucose is stress. The stress hormone adrenaline increases blood glucose, releasing it into the blood to provide a needed boost of energy to meet the fight or flight needs. In a situation such as being chased by a shark, we would react physically by fighting or fleeing and that glucose would soon be used up. But what if instead we remain stationary? Many of us deal with stress on a daily basis, but we don’t deal with that stress by engaging in physical activity. Instead, we are forced to sit and deal with it. One result of that inaction can be elevated blood glucose levels.

Cortisol is a hormone generated by the adrenal glands that can elevate blood glucose. Under conditions of high stress, cortisol provides the body with glucose by tapping into protein stored in the liver. This energy can help an individual in a fight or flight situation. However, if we’re constantly subjected to stress, the resulting chronic elevated cortisol can lead to increased blood glucose levels. To help reduce the effects of stress, we need to find ways to prevent or cope with it. Strategies include everything from exercise to nutrition, hydration, music and meditation.

Sleep is not a luxury — it is a necessity that also has an impact on blood glucose. In fact, a chronic lack of sleep is another form of stress that can result in elevated blood glucose, according to an article in the December 2015 issue of Diabetes Therapy. The National Sleep Foundation recommends seven to nine hours of sleep every night to enjoy its restorative health effects.

Another factor that can predispose individuals to Type 2 diabetes is a chronically low level of Vitamin D. A study reported in Scientific American in 2009, found that 45 percent of Americans are deficient in Vitamin D and more recent studies corroborate a rising trend in Vitamin D deficiencies. But here is the kicker: a Tufts-New England Medical Center study found that those who are chronically low on Vitamin D had a 46 percent increased risk of Type 2 diabetes. While the mechanism of Vitamin D with regards to diabetes is not crystal clear, researchers suspect that Vitamin D enhances the cells’ response to insulin.

As it turns out, precautions against skin cancer may actually be depressing our levels of Vitamin D. In a 2009 Article in Scientific American, co-author Adit Ginde, an assistant professor at the University Of Colorado Denver School Of Medicine, reveals that using a sunscreen with as little as an SPF 15 reduces the skin’s Vitamin D production by 99 percent.

As divers, we understand that hydration is a factor in decompression illness but it is also a factor when it comes to blood glucose levels. As fluid in our circulatory system is decreased due to dehydration, blood glucose becomes more concentrated. This causes an increase in urine production, which worsens the dehydration. The key message here is the importance of maintaining a healthy hydration level through consumption of water and other non-sugary beverages. Drinking water can reduce blood glucose, reduce insulin resistance and reduce hunger. If plain water isn’t enticing enough, try garnishing it with a citrus wedge, cucumber slice or fresh mint leaves.

Exercise is a double-edged sword when it comes to those with diabetes. In general, exercise is an important ingredient in maintaining health for those with diabetes. But for those with Type 1 diabetes, some precautions are in order. Vigorous physical activity should be avoided when blood glucose level is too high (hyperglycemia) and insulin level is too low. Not surprisingly, this precaution is reflected in the diabetic diving protocols.

Diving with Diabetes

While the long term effects of diabetes are daunting, the short term effects for a person with Type 1 diabetes can be downright frightening, especially if that individual should be underwater. The effects of hypoglycemia include confusion, blurred vision, impaired judgment, physical impairment, seizures and loss of consciousness. Such conditions are dangerous not only to a diver, but also the diver’s buddy. What’s more, if the symptoms aren’t recognized and properly treated, the diver could be in grave danger.

Steve Prosterman is a Dive Safety Officer at the University of the Virgin Islands and a Hyperbaric Chamber Operator at the St. Thomas Hospital. Diagnosed with Type 1 diabetes in 1967, he became a dive instructor in 1982 and has made well over 10,000 dives with no complications. As he points out, “The main risk of diving and diabetes is the sudden loss of consciousness or altered state of consciousness due to hypoglycemia (low blood sugar). Hypoglycemia generally begins to develop symptoms when the blood sugar falls to 60-70 mg/dl and lower and can also lead to impaired judgment, physical impairment and seizures. For this reason, anyone with a history of reactions with these symptoms should not dive.”

At first blush, we might think that diabetes is an absolute contraindication to diving due to the risk of losing consciousness underwater. But according to the Divers Alert Network (DAN), individuals with diabetes who wish to dive, can dive safely in many cases. In fact, protocols for diving with diabetes have been around for more than a decade now. The caveat is that medical screening and safety protocols must be observed.

According to DAN, the first step for the prospective diabetic diver is to undergo the same medical fitness evaluation as other candidates to ensure no other disqualifying conditions exist. These include such conditions as epilepsy, pulmonary disease, heart disease and others. A person who has advanced diabetes and suffers from secondary complications may also be excluded.

Next, it must be determined that no complications of diabetes exist that may increase the risk of injury while diving. DAN’s guidelines also note that candidates should be 18 years or older (≥16 years if in special training program), with a well-established treatment history and the ability to maintain blood glucose levels efficiently throughout the course of changing demands of daily activities. Those who do not have the ability to control their diabetes (read more here) can be at risk and may not be good candidates for diving. Candidates and divers with diabetes should undergo a mandatory annual medical examination and, if over age 40, should be regularly evaluated for silent cardiovascular disease.

General precautions for diving with diabetes include limiting depth to 100 feet (30.5 m), limiting bottom time to one hour and not diving beyond the no-stop limits. It’s also recommended that diabetic divers buddy up with non-diabetic divers and that their buddy be aware of both their condition and the proper procedures to recognize and deal with a hypoglycemic episode.

Since the primary risk comes when a diabetic diver experiences a low blood glucose condition, one key to safe diving is ensuring the blood glucose is at minimum safe level — and stable — at the beginning of a dive (see sidebar). The blood glucose must be high enough prior to starting a dive that the dive can be completed without experiencing an unsafe drop in blood glucose. Measuring blood glucose is quick and easy using one of the many blood glucose monitors available on the market today. Continuous glucose monitors (CGMs) are also available to help monitor blood glucose levels and trends.

Food Sense for All

Good nutrition is important to everyone’s health and can help prevent the onset of such diseases as Diabetes. For those who suffer with Diabetes or pre-diabetes, staying healthy is, in part, a matter of making the right choices when it comes to dietary intake.

Sugars and other carbohydrates are readily converted to glucose, but the rate at which that occurs is measured by something called glycemic index. A high glycemic index indicates a food will rapidly be converted to glucose, causing a rapid spike in blood sugar. A low glycemic index means that the digestive process for that food is slower, meaning a slow production of glucose and a slower rise in blood sugar. For example, white rice rapidly converts to glucose and has a glycemic index of 72, whereas an apple, which converts much more slowly, has a glycemic index of only 36. However, the glycemic load, which includes the effect of typical portion size, may be an even better measure of a particular food’s effect on blood glucose. (See sidebar.)

Another factor that contributes to the rise in blood sugar is the quantity of food eaten. Eating smaller portions results in lower spikes in blood sugar. For those with pre-diabetes or Type 2 diabetes, simply eating smaller portions more frequently can improve the body’s ability to maintain blood sugars in the proper range. Choosing foods with a lower glycemic index and eating healthy portions, can help keep blood glucose in the normal range.

One area of conflicting research centers on the effects of caffeine on blood glucose. A study published in the June 2016 issue of the European Journal of Nutrition found that the risk of developing Type 2 diabetes was reduced for healthy, regular coffee drinkers consuming three to four cups of coffee per day. However, previous evidence suggests that high doses of caffeine can cause blood glucose to spike. The Mayo Clinic suggests that consuming up to 400 milligrams (mg) of caffeine (about four 8-ounce cups of coffee) is safe for most people, but it can cause trouble (spikes or lows) for those with diabetes. Limiting caffeine intake is a likely a good strategy for improved health.

Considering the health effects of Vitamin D, all divers should strive to maintain healthy levels of this vitamin. Many foods are Vitamin D-enhanced and may have a naturally high dose of Vitamin D. These include salmon, tuna, mackerel and vitamin D-fortified dairy products. Taking Vitamin D supplements is another health-wise strategy that could help maintain pancreatic function and help control blood glucose. The advice of nutritionists is to take Vitamin D3 with a meal that contains fat, since Vitamin D is fat-soluble and this enhances uptake. Foods rich in healthy fat include fish, nuts, avocado and olive oil.

The more we learn about human physiology, health and the effects of the underwater environment, the better prepared we are to make safe adaptations to explore the underwater world. Unfortunately, not everyone can safely enjoy scuba diving, but for many of those with diabetes, the door has been opened with safe diving protocols based on solid scientific research.

Considerations for Candidates

While the criteria for diving with diabetes may vary from one certification agency to another, some of the basic criteria for safe diabetic diving include good control of blood glucose levels and freedom from severe secondary complications of diabetes. As University of the Virgin Islands Dive Safety Officer and Instructor Steve Prosterman points out, “A candidate for diving should have an understanding of the relationship between the disease and exercise, be able to recognize early and handle low blood sugars on their own and not have had a serious hypoglycemic (low blood sugar) episode within the last 12 months.”

One way that diabetics can measure their ability to control the disease is with a hemoglobin A1C test, which provides a 90-day lookback at blood glucose levels and is a good indicator of how well blood glucose is being controlled. Most doctors will recommend that this test be performed at least twice a year. For diving, it may be suggested that the test results be within 30 percent of the normal range. Results that fall outside that range may indicate that better control of blood glucose is needed before a person undertakes underwater activities such as scuba diving.

Also important to safety is the person’s ability to recognize the early warning signs of hypoglycemia. Divers with diabetes must have a clear insight into the relationship between diabetes and exercise and be able to recognize and respond properly when a low blood glucose situation is developing.

Glucose Management: Procedures for Diabetic Divers

Safe diving for diabetic divers requires strict protocols, as well as the development and use of good practices and habits. DAN recommends that divers make a general self-assessment of their fitness for diving on the day of the dive, as well as maintaining good hydration throughout the days of diving. Specific protocols* for glucose management on the day of diving include the following:

§                             Before entering the water, blood glucose (BG) must be stable or rising with a value greater than or equal to 150 mg dL-1 (8.3 mmol L-1). Divers should complete a minimum of three pre-dive BG tests — performed at 60 minutes, 30 minutes and immediately prior to diving — to evaluate BG trends. It is noted that alterations in the dosage of oral hypoglycemic agents (OHA) or insulin on the evening prior or day of diving may help.

§                             Divers should delay the dive if BG is less than 150 mg dL-1 (8.3 mmol L-1) or greater than 300 mg dL-1 (16.7 mmol L-1).

§                             Divers must carry readily accessible oral glucose during all dives and have parenteral glucagon available at the surface.

§                             If hypoglycemia is noticed underwater, the diver should surface (with buddy), establish positive buoyancy, ingest glucose and leave the water.

§                             Check blood sugar frequently for 12-15 hours after diving to ensure safe levels.

§                             In order to establish best practices for future diving, diabetic divers should log all dives and include BG test results and all information pertinent to diabetes management.

§                             For more information, contact DAN and consult your physician.

* Divers Alert Network, Guidelines for Diabetes and Recreational Diving, Proceedings Summary | DAN/UHMS Diabetes and Recreational Diving Workshop.

Also available from DAN: Pollock NW, Uguccioni DM, Dear GdeL, eds. Diabetes and recreational diving: guidelines for the future. Proceedings of the UHMS/DAN 2005 June 19 Workshop. Durham, NC: Divers Alert Network; 2005.

Symptoms of Hypoglycemia

Hypoglycemia is a condition where blood glucose (blood sugar) is low. When levels fall to 60 to 70 mg/dl or less, a dangerous condition exists. Some signs and symptoms of hypoglycemia of which diabetic divers, their buddies and instructors should be aware include:

§                             Excessive hunger

§                             Weakness or dizziness

§                             Confusion

§                             Unresponsiveness or inappropriate responsiveness

§                             Blurred vision

§                             Glazed eyes

§                             Sudden mood changes

§                             Irritability

§                             Loss of consciousness or altered state of consciousness

§                             Seizures

Diabetic divers who display these symptoms should follow established protocols. This includes exchanging hand signals to identify the problem, ascending and stabilizing at the surface (both the affected diver and the buddy) and ingestion of carbohydrates by the affected diver. The divers terminate the dive and return to the boat or beach where a blood test is performed. Such events, along with blood glucose results and other details of the event, should be recorded for future reference.

Glycemic Index and Load

The glycemic index is a measure of how rapidly a food is converted into glucose through digestion. A high glycemic index means a food converts quickly. The glycemic load is a measure of the impact of a typical portion of the food on blood glucose, taking into account the typical portion size. The values shown in the table below are just a few examples to give you an idea of how foods affect blood glucose and some are quite surprising. As the data suggests, even minor adjustments to diet can have a large impact on blood glucose control. Numerous online sources are available to provide values for a broad spectrum of foods.

 

https://www.tdisdi.com/diving-redundant-air-source/?utm_source=eNewsletterPro&utm_medium=email&utm_campaign=Do_you_dive_with_redundant_air%3F__5288&fbclid=IwAR1rwdf6ZnwUQR-mFcNi4efgHHQhAW3adYj9EUazsOLwhp6weFLUA1_UuOQ

 

Thanks to SDI/TDI and Mark Manthey for this article.

 

Diving with redundant air source for recreational divers

By Mark Manthey

Diving with an alternate air source (octopus) is something all divers do. However, not many recreational divers use a REDUNDANT air source. That is a completely independent air source (second cylinder, first stage, and second stage regulator set). For most recreational diving, your buddy is your redundant air source. However, in the Great Lakes region, where divers often dive below 100 feet in cold water, redundant air sources such as a pony cylinder are common, almost standard equipment for recreational divers.

So, where, when, and why dive with a redundant air source?

Should these dives be considered a technical dive? Now, that’s a great question, but we won’t address that here. Clearly, the ability to bailout of a dive, and to be self-reliant, gives divers in a catastrophic gas loss situation (such as second stage freeflow) more, better and safer options to surface safely without panic, without the assistance of a buddy.

·          Depth, due to the longer ascent time. At 130ft or, 40m, assuming a 30ft, or 10m per minute ascent rate, and a 3-minute safety stop, the total ascent time would be about 7 minutes. Depending on the gas loss rate, there may not be enough gas in the cylinder for the diver to safely surface.

·          Overhead environments such as a LIMITED penetration wreck dive, or ice diving. (This kind of diving may not require decompression)

Many options are available for diving with a redundant air source;

·          Back mounted doubles with a manifold. This configuration is favored by many technical divers. The manifold allows the diver to access the gas in both cylinders from a single regulator, and each cylinder has a first and second stage regulator. It may sound like overkill, but it’s a great setup, and I dive with them as a recreational diver often, on deep dives.

·          Sidemount. In recent years, sidemount configurations have gained popularity, and for good reason. Sidemount offers two independent cylinders, and easily accessed valves. Many sidemount divers use two 80cf aluminum cylinders, as they are widely available on nearly any dive boat, offering the diver 160 cubic feet of gas.

·          Single cylinder with H-valve. The H valve offers the redundancy of doubles, on a single cylinder. It’s compact and lightweight.

·          Pony cylinder. Pony cylinders come in a wide variety of sizes and mounting options. The key is to find the one right for your planned dive. Pony cylinders range from just two or three cubic feet, to 40 cubic feet. A small pony cylinder may be only good for a minute or two for deep dives but should be ok for bailout on shallow dives. In my estimation, its best to get larger pony cylinders. If you’re going to make the investment, you should give yourself the largest margin of safety for the money you spend. Pony cylinders have a variety of mounting options.

Again, you should choose the one right for you. Generally, they are either slung on the left side, or mounted on the right side of the divers’ main cylinder by a mounting bracket. I prefer to sling them. This allows the diver to easily manipulate the valve or hand off the cylinder to another diver if needed. A back mounted pony keeps the cylinder neatly tucked out of the way, and is favored by public safety divers, because it keeps it from dragging through the mud and muck they commonly find themselves in. However, this setup makes it difficult to manipulate the valve if needed.

Diving with redundant air sources offers safer and better options in an emergency, however, there are some issues that should be considered.

1.Plan your dive, dive your plan

First, there is no good reason for running out of air under normal diving conditions. Plan your dive, dive your plan. Use the rule of thirds and calculate a turn pressure that allows you to safely reach your exit point with adequate air pressure remaining. All divers should be in a position to surface with roughly one-third of their remaining gas pressure. Redundant air sources are for emergency use only and should not be used in calculating the depth and duration of your dive. If you need to use your redundant air source, the dive is over, and you’re in bailout mode.

2. Practice using it

Second, if you’re going to dive with a redundant air source, make sure you and your dive buddies are familiar with how to use it, and practice, practice, practice deploying it. Did I mention you should practice deploying, and using, a redundant air source? Ok, good. It is spooky how quickly learning how to deploy a pony becomes second nature. When diving with a pony, for example, I dive with the regulator charged and the valve shut off, to prevent an accidental gas loss. I make sure all my buddies know that if they need to use it, it will only have two or three breaths in the line until I can open the valve. I know some divers that always dive with their pony valves open. It’s not right or wrong, just a preference.

3. Valve shut off

Valve shut down is not a skill generally learned at the recreational level of diving. However, in a situation where a diver is having a catastrophic gas loss, I firmly believe it to be appropriate for the affected valve to be shut down. Shutting down the valve will save the remaining gas in the cylinder, and it could then be used later if needed. This also needs to be planned and practiced, practiced, practiced with buddies. I have had second stage freeflows myself, on occasion, and have assisted several divers with them. The freeflow is almost always caused by second stage icing due to cold water. Once the valve is shut off for a minute or so, the regulator has a chance to thaw, and will function normally again once the valve is turned back on. In my personal preference, I always position the cylinder on my BCD high enough so that I can shut down my own valve. A buddy may also assist with valve shutdown and opening. If the gas in the cylinder is simply allowed to deplete, the diver will lose the ability to power inflate their BCD or drysuit, once they reach the surface. They would then have to remember to orally inflate. This one simple thing could cause an already distressed diver to panic.

In conclusion, diving with redundant air sources allows a diver to mitigate some risk, however, they also come with risks of their own. I believe it is impossible to mitigate one risk without accepting a risk of one sort or another. Every diver must make that decision for themselves.

 

 thanks to Diver Training Magazine

https://dtmag.com

Keeping It Real: The Scuba Skills Refresher

By Barry & Ruth Guimbellot

 

HOW MANY TIMES have you thought about going on an exciting dive vacation, only to have something come up that pushes your plans farther into the future? Whatever the reason, your trip gets postponed and before you know it, you’ve been “dry” for a while. If you’ve been away from diving for several months or longer, we highly recommend visiting your local dive center to schedule a scuba refresher course prior to going on a dive trip. Fine-tuning your skills after a hiatus from diving is a wise decision that will help make your return to diving safer and more enjoyable.

Scuba Refresher: Dust the Rust Off

The first step to dusting the rust from your skills is to schedule a scuba refresher course with an instructor at a dive center near you. Your reviewing instructor will help you assess your current status and determine the level of review you’ll need in order to bring your skills up to par. The work needed to fine-tune your skills will depend on a few factors, including your experience level before the hiatus and the length of time you have been away from diving.

A typical scuba diving refresher course has two main sections. One section consists of reviewing the basic safety information you learned when studying for your certification. The second section involves performing basic scuba skills in a confined water setting. With the assistance of your instructor, you will be able to identify and practice the skills necessary for your level of certification. In general, the skills you’ll review in the skill circuit include underwater communication using hand signals, mask clearing, regulator removal, replacement and clearing, buoyancy control and swimming. Your instructor may also encourage you to practice air-sharing techniques often used when handling out-of-air emergencies with a dive buddy.

Underwater Communications

Good communication is essential for an enjoyable, safe dive. Learning appropriate hand signals makes communication with your buddy much easier, avoiding a great deal of frustration. If your memory on basic hand signals is a bit rusty, review them with an instructor or refer to your training materials. Basic hand signals include the OK sign, up/down signal and the out-of-air sign.

Mask Clearing

Nothing is more frustrating than struggling with a leaky mask — even if the reason the mask leaks is that you’re smiling a lot while diving. The skill circuit is the perfect time to practice clearing your mask. To begin, you will need to add water to your mask so you can practice getting it out. Do this by tilting your head slightly down and gently lifting a portion of the skirt away from your face. Allow a small amount of water to enter the mask. With the palm of one hand, push in and down on the top frame to hold it in place as you tilt your head back and exhale through your nose into the mask. The added air displaces the water, forcing it out the bottom of the skirt. When the water is gone, press in on the mask to seal it to your face.

Note: your instructor might show you a couple variations of the mask clearing skill. Use whichever method works best for you.

Regulator Removal/Replacement

If you have not dived in a year or more, how proficient and comfortable will you be at removing and recovering your regulator? This is an important part of any scuba refresher. Many of us are not at ease if our primary air source is unexpectedly dislodged from our mouth. To overcome this fear, practice this skill with your buddy or instructor by your side. First inhale a normal breath, then remove the primary second stage regulator from your mouth and hold in front of you with the mouthpiece facing downward. Immediately begin blowing a small, steady stream of bubbles. Developing the habit of exhaling a tiny stream of bubbles helps remind you not to hold your breath while on scuba, as doing so puts you at risk of injury. Clear the water from the primary second stage by exhaling through the regulator. You can also press the purge button on the front of the regulator to expel water.

The regulator recovery skill is a continuation of the removal/replacement skill. Performing this skill demonstrates that you know how to locate and replace the regulator. Remove the second stage from your mouth and let go of it while continuously exhaling a stream of small bubbles. Begin the sweep by leaning with the right shoulder downward. Allow the regulator hose to swing and hang away from your body. While continuing to slowly exhale, begin a downward sweep with the right arm, fully extending the arm behind you. Next, swing your extended arm out to the side and in front of you. The regulator hose should now be lying across your arm. The second stage should be close to your right hand. With either hand, grasp the regulator, put the mouthpiece in your mouth and immediately clear the regulator of water using either the blast or purge method. Resume breathing normally.

Buoyancy Control

Perfecting buoyancy control takes time and, if you’ve been away from diving for a while, this skill can get rusty. Two tips for better buoyancy include being properly weighted and having good breath control. After practicing this skill, test your ability by hovering in one position. In our example, the diver has lifted his legs and grasps each leg below the knee. If you are correctly weighted and using good breath/buoyancy control, you will be able to hover upright without falling forward or backward.

Swimming

If you haven’t worn fins in a while, it’s a good idea to do some practice laps in a pool. You can do this with just your snorkel gear. It’s also a good idea to do some surface and underwater laps while wearing a full set of scuba gear. You might want to practice managing a leg cramp, too, just in case.

As a reminder, if you experience a “Charley Horse”-type leg cramp of the calf muscle, grasp the fin tip and extend the leg while pulling the toes toward you.

Air Sharing

Being able to share your air supply with another diver could prove to be an important skill in an out-of-air situation. First, get the attention of your buddy by signaling you are out of air. Your buddy will either give you his or her octopus regulator or their primary second stage. If your buddy gives you their primary second stage, they will either start breathing off their octopus or the integrated BC second stage. Practice this skill as both the out-of-air diver and the air donor. In a real-life situation, once you and your buddy each have a supply of air you’ll hold onto each other and slowly start for the surface.

Even if you dive several times a year, a scuba refresher such as practicing this circuit before your trip is a great way to keep your skills sharp. Having proficient skills will make your dive experience safer and a great deal more fun.

For a more in-depth review of these and other skills, visit the Dive Training YouTube channel.

Story and photos by Barry and Ruth Guimbellot

Back Basics: Exercises to Keep Your Back Scuba-Ready

By Dive Training

Low back pain is a very common medical problem, estimated to occur in about two-thirds of adults. Because divers must move around a great deal, climb ladders, lift tanks, and be capable of self-rescue and assisting other divers in the water, back pain can be more than a nuisance for a diver. In some cases it can keep you out of the water.

Back pain can result from a variety of injuries or illnesses. The purpose of this article is not to help you diagnose the cause of your back pain. That task is best left to your physician. What I hope to accomplish here is to recommend exercises intended to minimize problems with back pain associated with the most common musculoskeletal causes. Before you begin any of these exercises, consult your physician or physical therapist.

Flexibility Training

The fundamental underlying principle is that it helps strengthen and improve the flexibility in your back, stomach, hips and thighs. It is important to balance strength and flexibility. For instance, if you exercise the hamstring muscles in your legs in such a way that they become tight (inflexible), the mere act of bending over may cause you to suffer a back injury. A back exercise program should be maintained on a regular schedule — at least every other day for starters and working up to twice each day. If you don’t keep up the program, and allow your muscles to become deconditioned and less flexible, then you will lose all the advantage you have obtained by stretching and exercising.

Begin each exercise routine slowly, with gradual stretching and lighter loads leading to more vigorous stretching and heavier loads. When you lift a load or exert, you should exhale. Inhale during the rest period between exertions. If you find yourself holding your breath while straining to perform an exercise, your breathing pattern is backwards.

The following are exercises and stretches to relieve back pain. Dress in loose-fitting, comfortable clothing. Equipment you’ll need: an exercise mat or beach towel, a chair. Repeat each exercise from five to 10 times:

Single knee-to-chest stretch – Lie on the floor faceup. Keeping one leg straight and your head against the floor, bend the knee of the opposite leg and pull the knee to your chest, using both hands locked behind the knee. You should feel your hamstring and hip stretch. Hold the stretch for 60 seconds, then pull your leg (still bent at the knee) out from the midline of the body, so that you feel a stretching sensation on the inside of your thigh. Hold this position for 30 seconds. Return your leg slowly to the floor and repeat this exercise using the other leg.

Double knee-to-chest stretch – Lie on the floor faceup. Bend both knees at the same time and pull both knees to the chest, using both hands locked behind the knees. Hold the stretch for 60 seconds, then pull your legs apart out from the midline of the body, so that you feel a stretching sensation on the inside of your thighs. Hold this position for 30 seconds.

Prone back extension stretch – Lie on the floor facedown with hands held against the sides of the body or on the forehead. Gently raise the head and shoulders from the floor and hold for a few seconds. If this is too difficult, place your hands on the floor near your head so that you can push up by straightening your arms. Keep your hips on the floor.

Standing back extension – Stand with the feet slightly wider than shoulder-width apart to maintain balance. Place your hands on your hips or against your lower back and gently bend backward at the waist. Hold this position for a few seconds.

Kneeling back arch (“cat” arch) – Kneel on hands and knees with arms forward of the head, palms on the floor. Tuck down the chin and arch your back upwards, while slowly leaning back on your heels and dropping your shoulders toward the floor. Hold for 60 seconds.

Standing hamstring stretch – Stand in front of a chair. Place one straightened leg on the seat of the chair. Gently stretch the hamstring of the straightened leg by slowly bending the other (balancing) leg at the knee. Try to hold the stretch for 30 seconds. Repeat using the other leg.

Standing calf stretch – Lean forward against a wall with both palms on the wall, heels flat against the floor. Place one foot forward to isolate the back leg, then lean until you feel a stretch in your calf muscles. Hold for 30 seconds. Repeat using the other leg.

Side-bend stretch – Stand straight, then bend at the waist to the side sliding the arm down the leg. Release the stretch and repeat to the opposite side.

Targeting Muscle Groups

The following exercises help strengthen different muscle groups related to back health:

Wall slide (back, hips and legs) – Stand with your back against a flat, smooth wall surface with your feet shoulder-width apart. Keeping your back against the wall, bend your knees toward a squatting position until your knees are bent to a right angle (90 degrees). Don’t squat beyond this position. Hold this position for a few seconds, and then slide back up to a standing position. The arms can be held at the sides or straight out in front for balance.

Prone leg raises (back and hips) – Lie on the floor facedown with your arms at your sides. Keeping one leg pressed against the floor, tighten the muscles in the other leg and raise it up a few inches for a count of 10, then lower it back to the floor. Keep your hips against the floor. Repeat this exercise for the other leg. A variation of this exercise is to place your arms extended in front of your head and raise the arm opposite the raised leg (e.g., left leg and right arm) at the same time.

Standing back leg swing (back and hips) – Stand behind a chair with your hands on the back of the chair. Keep one leg straight with foot planted on the floor while you raise the other leg backwards. Lower the leg slowly and then repeat the exercise with the other leg.

Supine leg raises (stomach and hips) – Lie on the floor faceup with your arms at your sides. Keeping one leg pressed against the floor, tighten the muscles in the other leg and lift it straight up 6-12 inches (15-30 cm) for a count of 10, then lower it back to the floor. Repeat this exercise using the other leg. You should feel a pulling sensation in the hamstring muscles of the lifted leg.

Sitting leg lift (stomach and hips) – Sit upright in a chair and lift one leg straight up to a position where you have a 90-degree angle at the waist, while keeping the other leg straight and lifted just a few inches off the floor. Repeat this exercise for the other leg.

Kneeling leg lifts (hamstrings, lower back and buttocks) – Kneel on the floor with your arms at shoulder-height for balance. Pull in one knee to your chest, then extend that leg straight behind you and lift it up slightly. Hold for 10 seconds. Repeat with the other leg.

Semi sit-ups (stomach “crunch”) – Lie on the floor faceup with knees bent and feet flat on the floor. Raise your head and shoulders slowly off the floor and reach toward your knees with your hands. Tighten the abdominal muscles. Hold the “up” position for two seconds, then release and slowly lie back down.

Back pain may be a symptom of a potentially serious situation. Inform your physician if your pain is accompanied by fevers, chills, unintended weight loss, difficulty with urination or bowel movement, pain or a tingling sensation in the legs or feet, or loss of circulation in the legs or feet.

To prevent low back pain, avoid risks such as heavy lifting (particularly while bending forward at the waist), sudden or forceful twisting of the torso, extreme body blows or vibration, jumps from heights, obesity and poor physical condition.

When Not to Exercise

Most therapists agree that it is not useful to begin exercises during the acute period when you have just suffered a back injury or have begun to experience pain. It is best to wait until the pain (and perhaps inflammation) has begun to subside, usually from seven to 10 days from the time that the pain has significantly improved. If you are controlling your back pain with pain medication, you must be particularly careful to wait to begin exercises until instructed by your physician or therapist.

Back-Saving Tips for Divers

Specific prevention measures for divers include:

When lifting any heavy objects, bend at the knees, not forward at the waist. This is particularly relevant when handling tanks and heavy luggage.

When donning a tank, let someone help you. Some persons like to lift a tank up over the head to slide it down their back so that they can slip their arms into the attached buoyancy compensator (BC). This puts extra strain on the back and neck, risks dropping the tank, and is much less stable than sitting or standing and having the tank carried into position by another person.

When wearing a tank, move very carefully when walking, particularly on a boat. It’s easy to lose your balance and fall or wrench your back. Try not to bend forward more than is necessary to maintain balance. Always hold on to something to maintain stability.

Be very careful ascending and descending ladders, particularly when wearing a tank.

Do a few stretching exercises before donning dive equipment before each dive.

Avoid sitting for prolonged periods. This is the anatomical position that is least favorable for low back strain, especially for those with chronic back problems.

By Paul M. Auerbach, M.D.

https://dtmag.com/thelibrary/divers-of-a-certain-age-scuba-diving-for-seniors/

Thanks to  Karen and Ian Stewart of Dive Training Magazine for the article.

Physical Fitness and Our Growing Waistlines

No matter your diving age, fitness is important. Just consider some of the activities you will need to do while diving. Can you do a surface swim in your equipment if you come up away from the boat? Can you physically get yourself into or out of the water before or after your dive? Could you help your buddy if they needed it? As we age our physical abilities decline and we may not exercise regularly or adequately. And like the rest of the country our waistline may be growing. Did you know that the average person gains about 3 pounds (1.4 kg) per decade starting at age 20? Being overweight may not itself be a restriction to diving but it may indicate a lack of physical fitness and certainly can put you at greater risk for cardiac incidents.

Being in poor physical shape as well as being overweight has also been shown to affect bubble formation after diving. You may remember from your training that bubble formation can be an indicator of your susceptibility to decompression sickness. In a recent study (J Appl Physiol. 2002 Oct; 93(4):1349-56. Ascent rate, age, maximal oxygen uptake, adiposity, and circulating venous bubbles after diving. Carturan D, Boussuges A, Vanuxem P, Bar-Hen A, Burnet H, Gardette B.), scientists found that “Younger, slimmer, or aerobically fitter divers produced fewer bubbles compared with older, fatter, or poorly physically fit divers.”

Being overweight can also put you at risk for Type 2 diabetes (noninsulin-dependent diabetes). Diabetes is usually considered to be a contraindication to diving by Divers Alert Network (DAN).

Is Age a Barrier to Physical Fitness?

We commonly assume that the older we get, the less we will benefit from exercise. However researchers have found that when it comes to improving the strength or endurance of our muscles, age is not a barrier. The cause of age-related differences in fitness appears to be the cumulative effects of our lifestyle choices. We choose to do less, and our bodies adapt. No matter what your age, if you reverse this downward trend you will see that your physical fitness and health will improve compared with others of the same age. Maintain your activity level, and fitness becomes easier to keep over time.

So how do we determine whether we are physically fit enough to do diving? Neal W. Pollock, the research director at DAN, in a 2007 article on fitness and diving, discussed measuring physical fitness by calculating aerobic capacity. Aerobic capacity testing is most commonly completed with treadmill running or stationary cycling. Pollock recommends that a diver be able to maintain a capacity of 10 MET (metabolic equivalent) or greater. A MET is the amount of energy being burned when a body is at rest, with the normal MET in a healthy population ranging from 5 to 25. A diver under relatively calm dive conditions can dive safely with a capacity of only 7 MET. But add in any challenges and that capacity might not be enough.

For more information on assessing your physical fitness to dive, see Alex Brylske’s “Are You Fit to Dive” article in the September 2010 issue of Dive Training.

My Aging Heart

Diseases of the heart and blood vessels are the leading cause of death in the United States and according to DAN one of the most common causes of fatal diving accidents. As we age the prevalence of cardiovascular diseases increases. From DAN’s 2008 Annual Diving Report it was reported that the 2006 collection of data included 75 scuba fatalities investigated by DAN. Of these cases, 38 percent were attributed to heart disease, with the majority of the victims being classified as overweight or obese by body mass index. Annual death rates for insured DAN members were stable during 2000-2006, with a mean of 16.4 deaths per 100,000 members. Fatality rates increased dramatically with age. Among divers 15-25 years of age, the fatality rate was less than 10 per 100,000 members but increased to 30 per 100,000 among divers 65 years of age and older.

High blood pressure is another factor to consider in assessing your fitness to dive. The average 60-year-old American male has a blood pressure of 140/90; 120/70 is considered normal. Chronic hypertension is associated with damage to the heart, kidneys and an increased risk of stroke. Antihypertensive medications, however, can help reduce the risk of serious illness. Most antihypertensive medications are compatible with diving as long as the side effects experienced by the diver are minimal and their performance in the water is not significantly compromised.

Physical activity on a regular basis will certainly help improve cardiovascular function. Make sure that you discuss any new physical program with your doctor before proceeding.

Is That In Focus?

As a photographer, one of the things I really notice with aging is the change in vision. My arms are no longer long enough for my gauges and seeing pygmy seahorses even with a viewfinder is more than difficult. As we get older, the closest point at which we can focus moves away from the eye about 0.4 inches (1 cm) per year. By the time we get into our 40s most people will be having some trouble reading. At this point the drug store reading glasses become our friend. Underwater you may be able to put your gauges on a retractable holder so you can pull them out to arm’s length or you may opt for corrective lenses in your mask. Several inexpensive options are available at your local dive store. These can include lens spots, lens bonded into your mask or even ones that adhere to your mask by water surface tension. And for spotting small stuff, we also carry an underwater magnifying glass.

Did He Say Go Right or Left?

As we age our hearing becomes less acute and for many of us this begins to affect our daily lives. The National Institutes of Health predicts that an estimated one-third of people in the United States between the ages of 65 and 75 and close to one-half of those older than 75 have some degree of hearing loss.

In diving hearing loss can pose a problem, especially during the dive briefing. You can miss important information about direction, timing, depth, conditions and safety factors. There are a number of easy steps to overcome this. Be sure to inform the divemaster that you are hard of hearing and may need for him to speak up or repeat things. Always confirm the dive plan with your buddy before entering the water.

Picking the Right Diving and the Right Location

As well as staying physically fit and maintaining a good diet, we can also alter our diving styles and locations as we age.

Both of us enjoy a “slow” style of diving not only because we are photographers but also because it helps us to conserve air and actually allows us to see more critters. We now try to find those dive operations that don’t enforce staying with the divemaster in a larger group. Many live-aboard operations fit this style of diving by giving you and your buddy the freedom to set your own dive plan and having the added benefit of limited gear handling. If you are diving with a day operation, it is important that you make sure that they know you and your buddy may drop behind.

As we have gotten older our choice of destinations has also altered. Places that offer good visibility, warmer waters, less current and easier shore access with shorter swims are more important to us now. We also have reduced the number of dives we do in a day. Our five-dives-a-day regime has given way to three or four dives, with more time for relaxing and socializing.

The Right Equipment

As with any sport, matching the right equipment to your physical needs is of great importance. Here are a few tips on how to synch your equipment with your aging diving aspirations:

Lighten the load. As we get older we lose strength and stamina. You can overcome this somewhat by reducing the weight of your dive gear. If your diving environments have shifted to less demanding conditions then you may not need a buoyancy compensator (BC) with as much lift capacity as before. Manufacturers have introduced many new styles that have reduced weight, are easier to carry and take up less space when traveling on a dive trip.

Smaller fins can also help. Stiffer, longer fins may be a thing of the past. Instead, like us, you may opt for some shorter and lighter full-footed fins. They are easier to pack, easy to put on and take off and don’t require a huge amount of energy to pump.

Lengthen your straps. Reduced flexibility comes with age. It gets harder to reach down and adjust those fins. Try looking for gear that makes it easier to deal with that lack of flexibility. Get fins that have large pull-tabs and that are easy to adjust. Look for options on wet suits that allow you to easily get into the suit — this may include extra zippers on the legs and arms.

Grow your gauges. As mentioned earlier it may be getting harder to see those gauges. Look for gauges and watches that have larger dials and are intuitive to read. An easy-to-read gauge will reduce a lot of unnecessary anxiety when checking air supply and time.

Roll your bags. Our bags seem to get heavier every year. Over the years we have reduced our footprint, lightened our load and added wheels. There are a number of choices out there today for wheeled duffels of all shapes and sizes. These bags make it a breeze for getting your dive gear from A to B.

Keep the core warm. Studies have found that the body’s response to cold changes significantly over a lifetime, with older people less able to maintain their core temperature at a given cold exposure than young people. You can help overcome this by staying warm, before, during and after the dive. Make sure you have the proper clothing to keep you warm before getting suited up for the dive (a hat helps). Make sure you have enough thermal protection to get you comfortably through the dive (a hood helps) and finally make sure you have clothes that will keep you warm after the dive.

The Incentive

There are challenges to diving as you age but there are also a number of psychological and physical benefits associated with continuing to dive.

Although diving may not be something that you do every day it can be an incentive to staying in good physical shape. And by being in good physical shape through regular aerobic activity such as walking, jogging, biking or swimming as well as muscle-strengthening exercises, we are more able to continue to perform the routine tasks of daily life. Stronger muscles also help to reduce the risk of falling and fracturing bones. Physical activity helps in reducing the risk of coronary heart disease as well as developing high blood pressure, colon cancer and diabetes. Studies have also indicated that physical activity is linked to improvements in positive psychological states such as confidence, well-being, mental energy and personal image. Although there is still much debate as to the reasons for these benefits, the overwhelming evidence supports the relationship between positive mental health and physical activity.

Diving can also be a very social sport. It is a great way to travel and meet new friends. Participation in social activities as well as physical activity help to reduce the severity or chances of developing disorders such as anxiety and depression while reducing the deterioration of cognitive functions associated with aging.

Your senior status may mean you actually have more time to devote to leisure activities like traveling and diving. Certainly diving can be enjoyed through your senior years. So stay active, eat healthy and get out there and dive.

11 Tips For Safe Diving

by Torben Lonne | 1 comment

Is scuba diving a dangerous sport? No, it’s not.

In fact, diving is considered to be safer than many other more conventional sports.

Despite what sensationalist news headlines suggest, the incidence of diving accidents is far less frequent than you might imagine.

And if you know your training and how to be a safe diver, the risks are minimal.

In order to qualify as a scuba diver you have to pass a medical clearance, and complete both theoretical and practical exams. Add to this the fact that modern equipment is both reliable and high tech, and you have all the ingredients for a safe sport.

PADI alone certifies nearly one million divers every year. So one can only imagine how many qualified divers there are out there. And yet, out of those millions, every year only approximately 1000 divers worldwide need decompression therapy.

It is true that a few scuba divers do experience accidents – some of them fatal. However, most of these are due to carelessness on the part of the diver, or overconfidence.

So here are 11 tips for all divers to keep in mind to ensure that they are diving safely.

1. Plan, plan, plan.

You’ve heard it before and I’ll say it again: plan the dive, and dive the plan. Planning a dive is vital when it comes to safety. Although this is particularly important for difficult or deep dives, it still applies to every dive that you do.

1. Verify the safety of your equipment.

Check your equipment a week before you plan to dive. Make sure everything has been serviced and maintained properly. Remember to check the batteries for your dive computer and underwater torch. When you arrive at your destination and are ready to kit up, you need to check that your equipment is working properly. If you are diving with a buddy, then check his equipment too and ask him to check all your gear as well.

1. Test new equipment in a controlled environment

It’s natural to be excited to test out a new piece of equipment. However, in the interests of safety it is always best to first test new equipment in controlled conditions. Your best option is to test it in a swimming pool. If that is not possible, then make sure that you use it during an easy shallow dive first. You don’t want to have to struggle with new equipment on a deeper dive.

1. Make sure you are ready to dive.

In addition to your equipment, your body needs to be ready to dive. If you are feeling ill or otherwise unprepared to dive: listen to the messages that your body is sending you. It’s more important to miss a dive because you’re not feeling up to it, than it is to take risks.

1. Find out about the current conditions (no pun intended!)

Before you dive you need to have an accurate assessment of the sea conditions. The surface conditions might affect the safety of boat launches, apart from anything else. The water temperature is important because that will determine what type of wetsuit to wear. Being too cold or too hot when you dive will be uncomfortable and might compromise your safety. Find out what the underwater conditions are. If there is extremely poor visibility, very strong currents, or other potentially problematic conditions then it might be safer to postpone the dive to another day.

1. Dive within your limits

Under no circumstances should you dive beyond your limits. If you are only qualified to dive to a certain depth, then ensure that the dive plan does not exceed that depth. This also applies to specialized diving that requires additional certification. Do no attempt something like cave diving unless you have qualified by completing the relevant certification. There is no place for ego or bravado here.

1. An alert diver is a safe diver

There is a reason why divers are cautioned not to drink alcohol for 24 hours before diving. You don’t want to have alcohol in your system when you dive because you need to be alert. If you are feeling hungover or very tired, it is not advisable to dive. You need to be alert and focused in order to dive safely.

1. Consult your gauges regularly

This might sound obvious but you’ll be surprised how many accidents occur because divers don’t adhere to this basic rule. If you are diving with a buddy, then let him know when you reach half your tank, and again when you reach your reserve. You and your buddy should from time to time ask each other how much air the other has left.

1. Know the dive signals

Marine life enthusiasts often get excited about learning the signals for different species. However, the most important hand signals are those pertaining to safety. Make sure that both you and your buddy understand a comprehensive array of signals. Not being able to convey messages accurately and understand each other underwater poses a potential safety risk.

1. Avoid colliding with a boat

Make sure that you always carry a marker buoy with you. Do not assume that boats can see you! Plan your ascent so that it is as close to your boat as possible. When you do your safety stop, make sure that you are at the recommended depth. If you don’t control your depth and buoyancy properly then you run the risk of doing your safety stop at propeller depth. (True story.)

1. Take responsibility

Even if you are diving with a buddy or even a team, you need to take responsibility for your own safety. It is up to you to ensure that you follow everything that you have learnt about safe diving. In this way you will avoid endangering yourself, or the other divers accompanying you on the dive.

Source: DIVE.in

5 Tips for the Best Safety Stop

By Travis Marshall April 12, 2017

Reposted from ScubaDiving.com website

Every dive should end with a safety stop. But being close to the surface makes buoyancy a challenge, and without the right technique, you might find yourself ascending unintentionally. Here are five tips for making safety stops look easy.

5 Tips for a perfect safety stop.

1. SLOW ASCENT Keep an eye on your computer or depth gauge to make sure you ascend no faster than 30 feet per minute. Remember to vent expanding air from your BC as you go, and always send up a surface marker if you’re ascending away from your boat.

2. PROPER POSITIONING Once at 15 feet, position yourself head-up and keep your depth gauge at chest level so your torso stays at the right depth.

3. STEADY AS SHE GOES If you’re holding a down line attached to boat, grab the line loosely with one hand, with your arm outstretched to prevent the line from pulling you up and down.

Always time your safety stop.

4. TIME IT Every diver should time his or her own safety stop — don’t rely on another diver.

5. SWIM SLOWLY Divers sometimes think once the safety stop is over, they can fin to the boat as fast as they want. But the final 15 feet are the most dangerous part of the water column for lung-overexpansion injuries. Ascend the final 15 feet at the same, slow 30-feet-per-minute rate.

If you’re like most divers, you’ve heard of — and perhaps adhere to — procedures that are considered “normal” within our sport. A few classic “always and nevers” include: always dive with a buddy; always do your deepest dive first; always wear a snorkel; never put your mask on your forehead; always end your dive with at least 500 psi remaining in the tank and — perhaps the number one scuba diving “never” of all time — never hold your breath.

At first glance, these might seem like black-and-white concepts. Except, guess what? They’re not. At least not entirely.

This might sound like I’m on the verge of committing scuba heresy, but please take a couple of deep breaths and keep reading, because in this article we’ll examine — and even challenge — several widely accepted “rules” of scuba.

Rulemaking 101

Human beings are social creatures. We essentially want to be accepted in society, to be viewed as normal. Without diving deep into sociological terminology, the concept of norms provides a key to understanding social influence in general and conformity in particular. Social norms are the accepted standards of behavior of social groups. Behavior that fulfills these norms is called conformity. Social norms often evolve into rules, which are defined as explicit or understood regulations or principles governing conduct within a particular activity. Rulemaking is one of the basic impulses humans have for organizing and simplifying actions.

Norms — and the rules that often evolve from them — provide order in society. These are some of the reasons why most people, most of the time, conform to social norms and abide by certain rules.

The thing about rules is that sometimes they are based more on folklore than fact. And sometimes rules change when new facts are revealed. Take Nitrox diving, for instance. When it was first introduced decades ago there was a big hubbub about it being a dangerous “voodoo” gas that could potentially kill divers. It was condemned by the major scuba diving magazine at the time and banned at popular dive destinations. Now we know differently and divers everywhere are safely using Nitrox.

Those who challenge social norms and set out to bend or even break the rules sometimes find themselves at the center of controversy. They often get branded as troublemakers and might even find themselves at odds with the law. However, these people also tend to be significant change makers.

Let’s examine some commonly accepted scuba rules regarding equipment and dive practices that might be worthy of bending. If nothing else, they’re worth pondering.

Equipment-Related Rules

Always wear a snorkel.

The snorkel is a required accessory for scuba diving students and their instructors to wear during training dives. But once certification requirements are fulfilled there are instances when wearing a snorkel attached to the mask can prove problematic. For instance, it presents a potential entanglement hazard when scuba diving in overhead environments, such as wrecks or caverns. In addition, it can create drag when diving in a current.

Still, a snorkel is a useful accessory when at the surface. In recent years several innovative scuba equipment manufacturers have developed flexible snorkels that roll up small enough to fit in your buoyancy compensator (BC) pocket and/or fold into their own “shell” carrier that clips to the BC. For this reason, I’d like to edit the “always wear a snorkel rule” to read, “always carry a snorkel.” When the dive is done and you’re ready for a surface swim, locate your snorkel, attach it to your mask and you’re good to go.

Guilherme Garcia photo

Never put your mask on your forehead.

Okay, this one is a pet peeve of mine. I wrote about it in the May/June 2016 Final Check column, titled, “What It Looks Like When … Safety is Your Best Practice.” Somehow, somebody got a whole bunch of divers believing that placing the mask on the forehead is the international signal for “diver in distress.” Except, that’s just plain wrong.

It is not uncommon for a panicky diver to jettison the mask and regulator. This action is a panic response, which is an indication, or a sign, that the diver is experiencing a problem. However, it is not a signal, as in “if you are having a problem, put your mask on your forehead to signal you are in distress.” If you surface from a dive and need help, signal, “I am in distress and need help” by waving one or both arms above your head. (It’s also a good idea to use an audible signaling device such as a Dive Alert™ or whistle.) There are plenty of instances when a completely happy, non-panicky diver might place the mask on his or her forehead without incident. That said, there are times when placing the mask on the forehead might not be a good idea, like when you’re in choppy seas. If your practice is to prop your mask on your forehead upon surfacing from a dive instead of leaving it in place, you run the risk of having the mask dislodged by a wave — and getting lost to the deep.

No gloves allowed.

Believe it or not, this is actually a hard-and-fast rule in many tropical dive destinations. In some locations, divers caught wearing gloves while scuba diving, face stiff penalties. (Fines may also apply to dive operators.) The idea behind this rule is that wearing gloves encourages divers to grab — and subsequently damage — delicate corals, whereas barehanded divers will think twice about doing so because they risk being cut by sharp coral or stung by stinging marine creatures.

I wholeheartedly support the environmentally conscious intent behind this rule. However, I do not agree with the practice of strictly prohibiting divers from wearing gloves. Some divers have medical issues requiring them to protect their skin from exposure to sunlight, have clotting issues that turn a simple cut into a medical crisis or run risk of infection due to a cut. These folks shouldn’t need a note from their doctor in order to be allowed to wear gloves while diving.

This month’s Final Check column, “What It Looks Like When … You Are Careful What You Touch,” addresses the potential danger of grabbing a marine-life encrusted mooring line during a safety stop. While no one associated with this magazine promotes the wanton destruction of marine life, we think the ban on dive gloves goes a bit too far. Instead, we’d like to see industry stakeholders continue to promote environmentally safe scuba diving practices that encourage divers to avoid touching corals, while still allowing them to wear gloves when needed. For instance, a diver can easily stash a pair of gloves in a BC pocket and retrieve them for use when grasping an encrusted mooring line during a safety stop.

Always turn the tank valve back a quarter- or half-turn.

Before entering the water, make sure you tank valve is turned all the way on.
Guilherme Garcia photo

This one’s been around forever. And it’s wrong. Don’t do this. Instead, always turn the valve all the way on and leave it that way. Do not turn it back at all.

Apparently, the reason this practice got started is because someone decided that divers might inadvertently “strip” the valve by attempting to turn it on after it was already on. Tank valves are pretty hardy. The chances that you’ll damage a valve are slim. However, if you partially close the valve and then descend to a deep depth, the partially closed valve could restrict the airflow from the valve, making it difficult for you to breathe while on a deep dive. To avoid having problems with restricted airflow at depth always turn the valve all the way on. You are more important than a tank valve. Never turn it back a quarter- or half-turn.

Ruling How We Dive

Never dive alone. Always dive with a buddy.

When recreational scuba diving first started, the relatively crude nature of early dive gear made it necessary for divers to help each other out. The buddy system was born of common sense. It’s hard for many new divers to imagine going on a dive without a BC, submersible pressure gauge (SPG), alternate (or redundant) air source or a dive computer, but all these devices were absent from early dive training. They simply hadn’t been invented yet. Keeping this in mind it’s easy to imagine why having a buddy was considered mandatory. In fact, buddy breathing — sharing one tank and regulator between two divers — was a critically important skill taught in early scuba classes. Over several decades, equipment advances have enabled divers to become safer. And more self-sufficient. Thanks to the development of alternate air sources and redundant air delivery systems, and the fact that buddy breathing itself could be inherently dangerous, the buddy breathing skill has been purged from today’s scuba diving training courses.

Where it was once considered risky and even foolhardy to solo dive, the practice is slowly gaining acceptance. Several major scuba-training agencies offer Solo Diver and/or Self-Sufficient Diver certification courses aimed at increasing diver independence and reducing an individual’s dependence on the buddy system.

However, despite advances in equipment and training, the issue of solo scuba diving remains controversial. Some industry experts argue that buddy diving can carry with it greater potential risks than solo diving. Some recreational divers agree, complaining about being randomly paired with a buddy they’ve just met. Some dive operators prohibit solo diving, insisting that their customers be in buddy pairs or teams, often on guided dives. Still other dive operators allow solo diving for those qualified and equipped to do so.

A word of advice for those who wish to solo dive on a charter: reach out to the dive operator in advance to discuss your solo diving preference. Be willing to provide proof of your solo diving experience. Recognize that the dive operator has the right to deny your request to dive solo and insist that you abide by their stated operational policies. If this is the case, you have the option to seek the services of a dive operator that welcomes solo divers.

It’s also important to note that in certain areas, such as city, county, state or national parks, solo diving might be prohibited. It pays to read the fine print when planning a solo dive inside park waters.

On a personal note, I’ve made my share of solo dives, usually on shallow sites not far from shore. I have enjoyed the freedom and solitude of solo diving without any problems. I think those who are willing to accept responsibility for their own safety as a solo diver should be respected rather than viewed as reckless.

No matter where you stand on the issue of solo diving, I think we all can agree that every diver should train and equip for self-sufficiency and be able to handle potential problems that might arise during a dive.

Always do your deepest dive first.

This rule was considered law for many years, and it is still widely practiced today despite the development of sophisticated dive computer algorithms and new research into decompression sickness. Dive Training’s Senior Editor Alex Brylske revisited this topic earlier this year in an article titled, “Deepest Dive First? The History and Science Behind How We Plan Our Dives,” which ran in the January/February 2017 issue. Here is an excerpt from Brylske’s article:

“The issue of reverse profiles is sometimes confusing because the term actually can have two meanings. First, a reverse profile can refer to a series of repetitive dives where the deepest is not the first in the series. On the other hand, it can also describe a single multilevel dive that doesn’t follow the ‘stair-stepping’ procured described earlier; and the diver finds him or herself in the deeper phase of a dive after completing a shallower segment. Both procedures violate the deep-first rule.

It may surprise you to learn that the deep-first rule is a relative newcomer to the diving liturgy, traceable only back to the 1970s. The story is also an interesting lesson in the history of scuba diving.

A popular assumption is that the recreational scuba diving community simply adopted the deepest-first rule from the US Navy. Such an assumption seems entirely reasonable given that the USN Tables were the first standard for recreational scuba diving. The problem is, it’s not true. The US Navy does not now, nor did it ever, have any prohibition against reverse profile diving. In fact, one of the example dive table problems an older version of the US Navy Diving Manual involved a reverse profile. Likewise, there is no such prohibition in commercial scuba diving. So where did the rule come from?

The first suggestion to make the deepest dive first appears to have been offered in a relatively obscure reference — and only as a suggestion — by a researcher named Dennis Walder in 1968. His rationale was that by making the deeper dive first, one might crush “silent bubbles” — assumed progenitors of decompression illness — making the development of bends less likely on that and subsequent repetitive dives. But this was based primarily on theory and informed speculation, not empirical evidence. Moreover, no reference to any deep-first guideline appeared in any recreational diving literature until 1972, when the following statement was published in PADI’s Basic Scuba Course Manual (a curriculum segment of the then-current PADI Instructor Manual): ‘One very important rule — WE ALWAYS MAKE OUR DEEPEST DIVE FIRST when using the dive tables.’ No rationale was provided, though examples were often included during training showing the aforementioned advantage of avoiding decompression stops.

By the 1980s ‘deep dive first’ was growing beyond a recommendation.

By the 1990s, the mantra of-deep first was firmly ensconced in diver training materials as well as in the psyche of divers; and no prudent diver even considered violating the warning. But by this time dive computers had become standard equipment, and whether by accident or intention, divers were making — and getting away with — repetitive and multilevel reverse profile dives.”

Brylske sums it up by saying, “In all probability, the deep-first rule might never have been challenged had it not been for the widespread use of dive computers. Although the rules say otherwise, no dive computer in existence explodes, calls the police or ceases to function if the user engages in a reverse profile dive.”

Always end the dive with at least 500 psi remaining in your tank.

This statement is uttered during practically every pre-dive briefing in locations all over the world. The rationale behind it is solid; divers should plan their dives well and monitor their gauges carefully to avoid running low on — or out of — air. And responsible dive guides should remind divers to monitor their air supply to avoid an out-of-air emergency.

However, in some instances, well-meaning but overzealous divemasters might take it a bit too far. I’ve heard divemasters jokingly “threaten” divers with penalties, like, “You’ll owe me a 6-pack,” if they surface with less than the mandated 500-psi.

If a diver is nearing the end of a dive and needs to consume air below the 500-psi mark in order to complete a safety stop, the diver should feel comfortable doing so without fear of reprisal by the dive crew, because there’s simply no place for shaming in scuba diving.

Never, ever make contact with the bottom.

In some instances, making contact with the bottom is considered an acceptable practice.
Guilherme Garcia photo

If you haven’t wanted to burn me at the stake by now, here goes. Over the years we have occasionally published photos of divers kneeling on the bottom. This usually results in a flurry of reader letters calling Dive Training out for promoting bad diving practices. Most recently, in the July/August issue, we ran cover photos that feature two divers standing/kneeling on a sandy bottom while on a shark dive at the famous “Tiger Beach” dive site off Grand Bahama Island. I am one of the divers pictured in the photo. I’m not sure where or when the “never touch the bottom” rule got started, but I can assure you there are several instances in which kneeling in the sand is an accepted practice. Tiger Beach is a perfect example. The site is shallow (less than 30 feet [10 m]), there’s usually a moderate current running — and the water is filled with sharks. For these reasons, attempting to stay neutrally buoyant, kicking hard against a current while hovering a few feet off the seafloor and keeping an eye on the sharks would be impractical — and potentially dangerous. Here, kneeling in the sand is the best practice. Dive operators in other parts of the Bahamas, Fiji, Tahiti, the Maldives and other popular dive destinations follow this practice.

Those who teach underwater photography know it is better to position beginning photographers in a sandy patch adjacent to a reef than to have them crashing into the coral while just starting out with a camera. Yes, the sand biome contains marine life, but in most instances it is not as delicate as fragile corals. A diver who carefully settles on a sandy area will have minimum impact on the environment.

In parts of the world where strong currents are common, dive operators instruct divers in the use of “current hooks” as a means of having minimum impact on the environment. A current hook, as its name implies, is a large hook attached to a short length of line with a clip at the other end. The clip attaches to a D-ring on a diver’s BC. Divers learn to hook into an area of coral rubble in order to stay put in a strong current. By using the hook, they avoid grabbing the bottom with their hands.

Here’s one more real-world “contact” scenario: If a diver accidentally ventures too close to the reef, rather than kicking to attempt to move farther away, using a one-finger touch of a dead or algae-covered section of reef to carefully push up and away from the reef is likely to prevent the diver from damaging living coral.

The “look but don’t touch” mantra is ideal, but there are instances when it’s not always practical. What I’m suggesting here is careful and conscientious contact with the bottom (and with dead sections of coral) when conditions warrant it.

Always breathe continuously. Never hold your breath.

As I mentioned earlier, this is arguably the “number one rule” of scuba because breath holding while scuba diving can lead to serious injury, even death. However, there’s a however here.

I bring it up in honor of a diver I met years ago. We’ll call her Janet. I guided Janet on her first recreational dives after she got certified. She bought a weeklong dive package and her first day of diving with the dive center where I worked went flawlessly. The conditions were perfect and Janet appeared comfortable in the water. I took a few underwater photos of her, smiling and signaling “OK.” She said she had a great time.

The following morning, she was waiting at the dive shop very early when I showed up for work. She told me she wanted to cancel her dives. When I asked why, Janet explained that she’d been awake most of the night because she was worried that she might have accidentally held her breath at some point during the dive the previous day. She said, “My instructor drilled it into our heads, ‘If you hold your breath, you will die,’ and I’m just afraid. I can’t remember if I held my breath or not, but I don’t want to die.” I explained in great detail why divers should breathe continuously and avoid holding their breath. When I was finished, Janet decided not to give up on scuba diving after all. She sat out the morning dives in favor of some sleep, but was back out on the boat later that afternoon.

So, here’s my little secret about breath holding while scuba diving. I often do it when taking underwater photos. I admit this not to encourage any diver to adopt the practice of holding their breath while on scuba, but rather to add some clarity to the breath-holding issue. If you’re like me and you sometimes briefly hold your breath while stationary, it is unlikely you will risk a lung-expansion injury. The key here is the word “stationary,” as in remaining in place and not ascending. If you hold your breath while ascending, you do indeed put yourself at risk of a potentially serious and possibly fatal lung-expansion injury. This is why scuba instructors drill it into students’ heads to “breathe continuously and never hold your breath.” But if you’re like Janet and you might have briefly forgotten to breathe continuously just for a second, say, when posing for a photo underwater, chances are, you’ll be okay. Still, do as your instructor insists. Breathe continuously and avoid holding your breath.

MaFelipe photo

A Question for You

If you’ve read this article all the way to the end, thank you. I hope you found it thought provoking. However, the take-home message I wish to leave you with isn’t about following rules. It’s about asking questions. Asking why we divers do or don’t do certain things is important. It’s how we learn and understand and it’s also how we grow. Not everything is black and white. I want to encourage you to ask the questions and find the answers and then question the answers if they don’t sound right. This is ultimately how we advance our sport, making it safer and more enjoyable for all. 

Courtesy of Dive Training Magazine. 

 

Hello all,

     With the recent closures of area beaches from possible Red Tide and the issues of Green Algae, we need to take consideration as to possible health issues when diving.  Here is a 2011 article from Alert Diver Magazine on health considerations when diving. 

Microbial Hazards

By Michael Miller, Ph.D., and Petar Denoble

A threat to scuba divers?

The hazard of human infection for those exposed to the sea has been known for a long time, but the public is becoming more aware of it as new evidence of the oceans' rapidly deteriorating health emerges. Even the most pristine seawaters are inhabited by large numbers of microbes.

Most of them are harmless to humans, but some, like the vibrio species, can make people sick or even kill them. Increased pollution, warming and acidification of the oceans, all of which cause the death and extinction of fish and coral species, also promote the growth of indigenous microbes and increase the concentrations of terrestrial pathogens. Pollution and microbial hazards are greatest in coastal waters; unfortunately, this is where most recreational activities occur.

Routes of infection

Indigenous and introduced microbes may cause illness in humans either by infection or indirectly by intoxication. The sheer volume of seawater and its constant movement usually dilute foreign microbes below concentrations necessary for human infection. But there are many conditions when critical concentrations may be reached or when the threshold for infection in an individual is lowered. The greatest risk for human health comes from consumption of seafood.

Human potential for contracting diseases from pathogens in the marine environment depends on exposure time, the virulence of the pathogens and the susceptibility of the individual. Microbes generally infect humans through ingestion, inhalation or mucous-membrane exposure (naturally occurring or in wounds). Microbes can infect through injured skin, the ears and the mucosa of the mouth, eyes and nose. Infections may also result from swallowing water. Nonfatal drowning in marine environments brings seawater into the lungs and can result in pneumonia. Some hazards like aerosolized bacteria, generated in coastal environments by wave activity, can transmit algal toxins to humans and cause viruses to become airborne. This type of hazard is less likely to cause illness in divers than swimmers, thanks to masks and regulators.

Risk of direct infection by microbes from seawater is very small. However, the risk increases significantly in warm, brackish waters, in waters proximate to sewage and run-off inlets, at places of animal access and at populated beaches Divers may acquire dive-specific infectious diseases from exposure to the marine environment or as a result of close contact with other people and their dive equipment. If equipment is not properly cleaned, dried and stored after use, colonies can grow and microbes can reach sufficient numbers to infect users. Paradoxically, efforts to protect equipment from the corrosive effect of sea salt may also result in unwanted risks to divers' health.

Communal culprits

Communal rinse tanks have been shown to concentrate bacteria, so rinse
gear that comes in contact with skin — and especially mucous membranes
— under running water when possible.

Most dive operations offer some kind of communal fresh-water tank for the postdive rinsing of equipment. Generally there are tanks for rinsing wetsuits, masks, boots, regulators and buoyancy compensation devices (BCDs) along with separate tanks for photo equipment. Despite the best of intentions, such a system may demonstrate more care for camera equipment than for human health. The volume of dive gear passing through rinse tanks in a day may significantly exceed the volume of water in it. Because of the inequity, rinse tanks become the means for collecting and concentrating microbes from all users, creating the potential for spreading infections among them.

In 2007, a research team under Michael Miller of West Virginia University embarked on a study to sample water from communal rinse tanks and check it for the presence of bacteria. The first test was conducted at a popular Caribbean dive destination. For four days, the team collected daily water samples from communal rinse tanks after they were first filled in the morning and again several times throughout the day. They divided small amounts of the water samples onto agar plates and subsequently observed bacterial growth of different morphologies and swimming patterns. They did not attempt to identify the bacteria during this phase of the study and, therefore, did not determine if any were harmful to humans. This preliminary research simply confirmed the possibility of significant bacterial presence in rinse tanks.

Several months later, a similar study was undertaken at a dive facility on another Caribbean island. The operation's two boats each had two rinse tanks: one for wetsuits and BCDs and another for masks and regulators. The operator fully cooperated with the study; for five days the wetsuit tanks were drained each morning, and one of them was cleaned with bleach before they were refilled. The team took water samples from both tanks at that point and again at multiple times throughout the day.

Notably, this facility also allowed the sampling of water from the pipes used to fill the tanks, an opportunity not previously afforded the team. Tests showed the water used to fill the tanks was free of bacteria, nor were bacteria detected in either tank immediately after they were filled in the morning. However, by the afternoon all three tanks contained a lot of bacteria of many different types. Precleaning with bleach did not impact bacterial contamination. The two mask rinse tanks on the boats were also sampled, and both of these contained very high levels of various, unidentified types of bacteria. The time pattern of the findings indicated the bacteria were rinsed off of the diving equipment, but it remained unknown whether they originated from the sea or from divers as well as if they were pathogenic.

Finding the answer

Public health officials measure levels of certain species of bacteria to evaluate the risks to humans in many popular recreation areas.

In June 2008, the team performed a third study with the aim of identifying bacteria in rinse tanks along with their source. The study was done at yet another Caribbean dive resort. Water samples were collected from the hose used to fill a communal rinse tank, the rinse tank itself, buckets on the boats in which masks were rinsed and stored, several dive sites in the ocean at various depths and, finally, ocean water near shore at the dive facility. Again, the water used to fill the rinse tanks was found to be safe. But this time the bacteria that developed throughout the day were identified, confirming that some likely originated from the ocean and others from the divers themselves.

None of the identified bacteria would be considered overt human pathogens, but some are considered opportunistic pathogens: They could infect individuals with compromised immune systems or may infect open wounds. Bacteria identified in the communal rinse tanks are generally associated with unsanitary conditions. Where these bacteria are present, other pathogenic bacteria may occasionally occur. The scope of the study did not include checking for viruses usually found along with bacteria that may cause serious diseases.

In the eye of the infected

In March 2006, a group of 27 health-care providers attended a conference at a dive resort in the South Pacific. On the second day of diving, two divers reported eye problems, and over the next few days 13 divers (roughly half of the group) were diagnosed with conjunctivitis, an inflammation of the eye. It is characterized by the sensation of a foreign body in the eye, redness of the mucosa and possible discharge. Conjunctivitis of viral or bacterial origin spreads easily from person to person through close contact. There was an outbreak of conjunctivitis among the local population, but the divers did not have much contact with them.

Two physicians from the group investigated the spread of the conjunctivitis among the divers. They concluded the conjunctivitis originated from a divemaster who had an eye infection prior to the diver outbreak. The divemaster placed his mask in a communal container of diving masks, which apparently became the means by which conjunctivitis was spread among the divers. Only divers who used this tank were infected. Those who did not use the tank were not infected despite close contact with those who were.

To prevent further spread of infection, divers used bleach and detergent for mask cleaning. Affected divers received antibiotic drops and ointments and were healed in the next several days. One diver manifested symptoms after returning home. This case study demonstrated that disease can be spread among divers using communal rinse and storage containers. Conjunctivitis is a disease with short delay from infection to symptom manifestation, which made it possible to identify the source of infection. Other infections may have been transmitted by the same means, but due to longer periods of incubation as well as occurrences after the divers returned home, the link to communal tank was missed.

Based on the lack of reports, the risk of infection by means of communal rinse tanks appears negligible, however, it's possible divers incorrectly attribute such infections to other sources. Miller's findings and the report of the conjunctivitis outbreak indicate communal rinse tanks may serve as avenues of infection transmission between divers. When it comes to rinsing dive equipment in direct contact with divers' skin and mucous membranes, such as masks and regulators, instead of using communal rinse tanks, divers are advised to clean gear using disinfectants under running water.

Other areas of consideration

Besides rinse tanks, there are at least three additional areas in which infections may spread among divers: the common, the rare but dangerous and the feared but unlikely. The most common infections reported in diving are otitis externa (swimmer's ear) and skin infections (impetigo and others). Fortunately, these can be easily prevented, diagnosed and successfully treated.

On the other hand, diving or swimming with an open wound may result in a rare, but often fatal, infection with Vibrio vulnificus, an opportunistic pathogen commonly found in warm coastal waters. The Centers for Disease Control and Prevention receive approximately 150 reports each year of people infected with V. vulnificus, most by eating oysters and a few through open wounds.

Some divers fear sinusitis and cystitis (bladder infection). Indeed, swimmer's sinusitis has disrupted the careers of many aspiring athletes. However, it is most often caused not by microbial infections but by chemical irritation from chlorine used to disinfect pool water. It does not occur in ocean swimming. Indeed, some people with chronic sinusitis maintain that swimming in the sea and flooding their sinuses with salt water helps, a notion seemingly supported by an increasing number of ear, nose and throat physicians who advise patients to use saline sinus rinses to relieve nasal and sinus congestion. However, it's important to remember that the intentional or inadvertent introduction of seawater into the sinuses could cause infection if the introduced water is loaded with a sufficient number of pathogenic bacteria or viruses. It is difficult to come by any such cases in conventional medicine literature.

The effect of swimming on cystitis in women is a popular topic of discussion in the media. The prevalence of cystitis is very high, and in many cases it is recurrent. Each occurrence often is the result of infection by a new causative microbe. Chemical irritation from chlorinated water or the prolonged wearing of a wet swimsuit may enhance the recurrence of cystitis, regardless of the bacterial contamination of fresh or salt water. When it comes to cystitis, it may be a predisposition rather than a specific causation that affects its occurrence.

Putting it in perspective

While it seems there are many microbial hazards in the sea, the true risk of serious infection to divers seems negligible. Most infections that may be occurring among beachgoers, swimmers and divers probably manifest as diarrhea, but that is so common among travelers it is rarely linked to seawater. The two most common infections in divers are ear and skin infections.

To mitigate risks of infection while diving, regularly clean and disinfect equipment, avoid polluted waters, never dive with open wounds (including tooth extractions) or sores, never rinse your mouth or sinus cavities with seawater, keep your ears dry, avoid prolonged wearing of wet clothing and shower after diving. Divers with an acute infection such as a common cold, conjunctivitis, skin infection or gastroenteritis are not fit to dive and must take precautions not to infect others.

Beach Bacteria

Waterborne disease outbreaks (WBDO) have been reported in people bathing in pools and rivers but not among seaside beachgoers. However, due to presence of the diarrhea-causing microbes on seaside beaches, epidemiologists assume that cases of gastroenteritis resulting from exposure to marine pathogens must be common, too. The summertime increase in occurences of gastroenteritis in coastal states indicates a possible role of beaches in disease transmission.

In 2009 and 2010, scientists discovered methicilin-resistant staphylococcus aureus (MRSA) in the sand of many beaches on both the West and East coasts. MRSA causes intrahospital infections with a high mortality rate due to its resistance to many antibiotics. MRSA also occurs outside of hospitals, but the source of infection is not known. Seasonal increases in MRSA infections coinciding with times of increased beach use may indicate beaches are a possible means of MRSA transmission.

Clean and Sanitize Your Dive Gear

By Daryl F. Stanga, HM1/SCW/DV, U.S. Navy

Although the risk is considered to be very small, second stages and mouthpieces could transmit disease. Divers are encouraged to disinfect equipment properly.

Commercial products designed for cleaning dive gear are widely available. Make sure to choose a cleaning agent that does not contain hydrocarbons. If in doubt about a product's usability on dive gear, consult the equipment manufacturer for recommendations.

To clean scuba regulators, use a scrub brush to remove any gross contamination such as mud, dirt, sand, seaweed or saliva from the regulator. Rinse thoroughly with fresh water, then spray a liberal coat of the chosen cleaning agent on and into the mouthpiece and second stage until all surfaces are wet.

Let stand for 10 minutes. If the solution appears to be drying, apply more to keep the regulator wet for the full 10 minutes. After 10 minutes, rinse with clean, fresh water or under running potable water.

If several regulators need to be sanitized at the same time, or if you prefer immersion to clean the equipment, regulators may be immersed in the disinfectant solution for 10 minutes and then rinsed in fresh water.

Use the same procedure to sanitize snorkels and the oral inflation tubes of BCDs. To clean the BCD thoroughly, pour several ounces of the solution into the bladder and agitate for 10 minutes. Then empty the bladder and rinse with fresh water.

Before reassembling, allow the BCD to air dry.

Public Health Policy

From a public health perspective, monitoring popular recreational areas for various indicators is one of the major steps taken in risk reduction. There were more than 24,000 beach closures and advisories in 2010, the second-highest number on record. The majority of these were due to the presence of bacteria. Scientists and public-health officials rely on several factors to determine whether risk of infection is elevated in a particular area.

1. Unsurprisingly, the presence of sewage is correlated with elevated infection rates. Gastroenteritis and respiratory illness in particular increase with the degree of site pollution. Pollution with sewage is generally assessed by monitoring the presence of enterococci bacteria.
   
2. High swimmer density is a second factor shown to increase infection risk. Elevated numbers of minor ear and skin infections from human-shed bacteria are observed where swimmer density is high. Skin granulomas from Mycobacterium marinum have also been observed. Staphylococcus aureus levels have been proposed as indicators of exposure.
   
3. Eutrophication, the increased abundance of algae, phytoplankton and other marine plants, may be linked to higher rates of infection by pathogens native to the marine environment. Runoff from agriculture and golf courses is a major cause of eutrophication. Blooms of plankton and algae can promote growth of associated populations of marine pathogens by increasing nutrients in the water and providing microenvironments that favor growth. The prevalence of Vibrio species has been proposed as an indicator for measuring eutrophication.
   
4. Elevated seawater temperature is associated with increased incidence of shellfish poisoning and cholera. Remote sensing of sea surface temperature is being explored, but its predictive value needs further study.

References

Miller MR, Motaleb M (2007). "Scuba divers rinse tanks harbor many microorganisms." Microbe 2(12): 577.

Olsson DJ, Grant WD, et al. (2008). "Conjunctivitis outbreak among divers." Undersea Hyperb Med 35(3): 169-74.

Thompson JR, Marcelino LA, Polz MF (2005). "Diversity, sources and detection of human bacterial pathogens in the marine environment" from Oceans and Health: Pathogens in the Marine Environment, Belkin S and Colwell RR (eds.).

Washburn BK, Levin AE, et al. "Identification of bacteria in scuba divers' rinse tanks." Undersea Hyperb Med 37(4): 233-40.

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© Alert Diver — Fall 2011