DEMA Show Update #3

The DEMA show is winding down, but there were still lots of great seminars put on by various manufacturers, dive travel destinations, and certification agencies. In particular, the seminars presented by DAN, the Divers Alert Network, have been particularly interesting and informative. We went to one today entitled How Physically Fit is Fit to Dive? presented by Dr. Neal Pollock, who is the research director at DAN.

Some highlights:

Dr. Pollock started out by discussing various types of “fitness to dive” including medical fitness, psychological fitness, physical fitness, diving knowledge, physical skills, and nutritional status. The biggest issues many divers face are physical fitness, and the need to be fit enough to meet the demands of a particular dive, but also have some reserve capacity to if exceptional demands occur on a dive, such as a sudden change in current or wave action, upwellings, etc. The exceptional demands will of course vary by the environment. As he put it: “You should be fit enough with a reserve to be safe for every dive”.

The next topic address was the rise of Body Mass Index (BMI) which is defined as a person’s weight relative to their height. In the 1960s through the 80s, the average BMI stayed relatively stable, while from the 90s through present day, BMIs are rising rapidly. The discussion turned to Metabolic Syndrome, which causes cardiac conditions and diabetes. Some additional information can be found HERE on risk factors for Metabolic Syndrome.

Diver fatalities were address next, and not surprisingly, smoking and obesity were common in dive fatalities. As would be expected, cardiac issues increase with age and are also a leading factor in dive fatalities. Dr. Pollock spoke of how divers die, with respect to age and gender. Young males tend to have a higher fatality rate than young females, due to what he called the “watch this” syndrome. As divers age, and especially once they reach their 50s and up, both genders’ fatality rates were very close due to common diseases in aging divers. We can expect a loss of 1% of our aerobic capacity every year after age 25-30.

Some things we can do as divers:

• Strength training using weights
• Aerobic training, like running, cycling, swimming
• Dynamic/flexibility training, such as doing yoga, playing volleyball or racquetball

It is recommended that we exercise 3-4 times per week, for 30-60 minutes per session, raising our heart rate to 60-75% of our max heart rate. To calculate max heart rate, simply subtract tour age from 220. The chart shown will help illustrate the point.

Another important point addressed was that of pre and post dive exercise. Dr. Pollock recommended that we isolate pre and post dive exercise to 24 hours to avoid the risk of causing decompression illness. The point here is that the exercise to avoid is what he called “high joint forces” exercise, like high intensity aerobics, running, etc.

As was mentioned, the seminars have been very educational, and Dr. Pollock referenced some additional websites that are worth mentioning here: Physical Activity Guidelines for Americans from the U.S. Department of Health and Human Services and Physical Activity and Health from the U.S. Surgeon General.

So, by being in better physical, medical and psychological fitness, as well as having and constantly improving our skills and education and knowledge we will help avoid injury during the sport we all love.