"Doing it Right"
Fitness for Diving
by Dan Volker
"Doing it Right" diving has led to world record penetrations and depth/duration records, with over 8000 man dives and zero deaths----in stark contrast to all other diving systems.
The fitness and nutritional requirements for those who desire to be a "safe" diver are amazingly similar to the requirements of an athlete. For good offgassing, there needs to be a high level of perfusion throughout the body. The diver needs to create much more developed capillary beds in ALL muscle tissue, and the vascular system in general will function better for offgassing, with more intensive cardiovascular training. Venous return with larger diameter veins and less restrictions, will clearly be advantageous as nitrogen or helium bubbling begins to populate the venous return with the challenge of increasing bubble diameter. Larger veinous systems and a more powerful cardiovascular sytem, will eliminate bubbles quicker, with less chance of bubbles impacting with each other and joining, and large venules will have less liklihood of slowing or impeding the migration of bubbles into the larger veinous return system.
From a Bill Mee post on this : "The problem is that these bubbles effectively block normal capillary plug flow. Plug flow is the phenomenon of red blood cells lining up behind each other and moving through the capillary in unison. If you get a tiny bubble forming at a capillary junction or a cross channel it can physically stop the flow and lead to ischemia in the tissues downstream. The same thing happens sometimes while filling your gas tank when you get an air pocket. At any instant the blood flow in about a quarter of the vessels is either stopped or sluggish. When you observe micro-cinematography of capillary beds you can see this process. Once you have these bubbles formed you need to both get rid of the bubbles(shrink them) and try to get oxygen to the tissues deprived of perfusion…."
Anti oxidizing agents, now common in sports nutrition, offer some protection for high partial pressure oxygen reactions, but can not be thought of as any mechanism for effecting changes to Oxygen toxicity.
From a Bill Mee Post : "Hyperoxic oxygen is perhaps the single most dangerous factor intechnical diving. There are many reasons for not exposing oneself to high ppo2s not the least of which are seizures and death. To recommend the breathing of high o2 mixtures is both frivolous and reckless particularly when the consequences of high oxygen exposure are considered. We know a lot more now about the consequences of high ppn2s and high ppo2. The WKPP drastically modified it's practices with regard to oxygen exposure following the collective experience of many lengthy decompressions and the varying levels of pulmonary distress. Once you are aware of the seriousness of what hyperbaric oxygen does you may wish to rethink how much exposure you care to subject yourself to. The Hemoglobin oxygen buffering system is a remarkable evolutionary adaptation which allows humans to exist at oxygen tensions substantially lower than what we encounter at sea level. Even with alveolar oxygen levels at 100 mmHg ( .133 Ata Ppo2) the hemoglobin is 97% saturated. This system unfortunately is incapable of maintaining the normal 40 - 60mm Hg capillary tissue tension when the alveolar po2 rises beyond 2 ata. When this happens the level of dissolved o2 (non hemoglobin bound) in the blood rises uncontrollably and with it the presence of oxygen free radicals such as the superoxide and the peroxide free radical. These oxidizing free radicals swamp the enzyme systems for removing them and have a serious destructive and possibly lethal effect on cells. Ordinarily, the body's system of peroxidases, catalases and superoxidedismutases mops up these radicals. Almost any college text on biochemistry broadly details the mechanism and kinetics of these reaction mechanisms. The vitamin E family (tocopherol isomers) is known to play an important role in this antioxidant management system. You will note that the alveolar tissue component is exposed to the direct effects of high oxygen without the benefit of the buffering system. This is probably why even moderate exposures of o2 at 1 ata and slightly above cause observable functional deficits (Clark and Lambertsen 1971 and Clark 1988).The first victim to go down, following the collapse of the hemoglobin-oxygen buffering system, are the polyunsaturated fatty acids that are fundamental components of cell membranes and connective tissue. Many cellular enzymes, both free and membrane embedded are oxidized, challenging many metabolic systems dependent on these enzymes. Neurological tissues are particularly vulnerable given the high lipid content of axonal, soma and dendritic structures in nerve cells. This probably accounts for the extremely acute damaging effects of hyperoxiaon brain function such as seizures. Other complex neurological tissues such as the eye and its components (retina) suffer quantifiable deficits. When you are honking on pure oxygen at 20ft and think that dropping down to 30ft will give you better results I suggest you seriously think again. Even worse don't even think about doing a working dive at 1.6 atappo2. For anyone who advocates diving at 1.8 ata ppo2 I say let them have at it themselves validate Darwin's theories of natural selection…." End Bill's post
The fitness regimen needs to address both the overall cardiovascular efficiency and power, as well as the level of perfusion throughout the body. Since most divers will be swimming throughout their dives, development of the primary muscles engaged in fin swimming will be a key to preventing bloodflow constrictions caused by utilization of a large percentage of primary muscle fibers ( constriction will be lower with less fibers engaged in contractions) ….and neo-vascularization needs to occur throughout the primary leg and hip flexor muscles, to allow for less restricted offgassing. In simpler terms, this means weight training in combination with aerobic training, to increase the bloodflow and work capabilities of your leg muscles.
Cycling for cardiovascular efficiency, combined with gym workouts which utilize high repetition supersets for the leg muscles, will be the general direction most divers should take for this aspect of their efficiency training.
Those who have the time to add lap swimming, as well as thorough upper body gym workouts, will further maximize perfusion throughout the body. Both the strength ( anaerobic) and endurance ( aerobic) …… To the degree you have an interest in maximum bottom time allowed without mandatory decompression stops, and repetitive diving, fitness becomes more important to your long term health as a diver. As you add liveaboard trips with 5 and 6 dives per day for several days to a week at a time, your fitness requirements are pushed much closer to the levels full blown technical divers require.
Expect this fitness section to be updated every 2-3 weeks, and to cover training plans, diet, supplements and goals. In the next few days, the "Dive Store" button on top will point to a few sites with additional diet or supplement information. Some will be non-profit sites devoted to pure information, some will be actual online retail sites who happen to carry hard to find products that I have found effective as training supplements. This is yours to ignore or utilize. The e-mail form below is for you to use to ask questions about training for fitness, diet, etc., and I would ask that you include a phone number with any complex questions, so that we can limit the back and forth e-mail issues a complex question can create. dlv@gate.net