Diving workout

[DRE]

Contrary to popular belief, the most important workout for a diver is the aerobic workout. Most people think because diving is 1) not a very aerobic sport, and 2) since hauling tanks is a an anaerobic activity that the most important workout for a diver is a weights routine.
Now, weight routines are important for the diver, no doubt about it. It does build strength to lift the heavy equipment, it strengthens the bone structure, which reduces the possibility of bone necrosis (something to worry about when you're doing long and deep exposures), and it builds lean muscle mass, which is far easier to offgas than fat tissue.
However, the aerobic workout is more important for several reasons. First, it improves the overall physical conditioning, which means the heart rate at rest is lower, which means your gas consumption goes down - thus, longer bottom times on a tank, or reduced gas consumption in a more strenuous dive. Secondly, being in better physical shape delays the onset of the panic response. The mind reacts emotionally to an increased heart rate, increasing physical activity. This becomes a loop system to the point where the diver will succumb to his efforts and become unresponsive. Third, physical conditioning increases lean muscle mass, thus better offgassing. Also, it improves the gas exchange ability of the lungs, so the aerobic fit diver will be able to offgas more inert gas with every single breath and send more O2 through the bloodstream than the unfit diver. And last, aerobic training increases the diameter of the blood vessels and increases the amount of pathways. This has two implications: bubbles when formed in the bloodstream won't get lodged as easily because of the larger diameter, and if they do get lodged the blood has different pathways to bypass the blocked area, thus reducing the chance of clinical DCS.

Therefore, aerobic training should be the primary concern of the conscientious diver. Personally, I do an aerobic workout 6 times a week, and a weights workout twice a week. The kind of workout isn't as important as the fact you do it, but at least a minimum of 30 minutes three times a week should be considered. Also try to do cross training: if you get bored with running all the time, or doing the stairmaster, try swimming, biking, rowing, jumping rope, cross country skying, etc.