Excercises for diving

By Dr. Sawatzky

Last month I continued a discussion on fitness and diving. We looked at the various aspects of fitness, how fitness is measured, and many reasons why divers should be fit. This month we will finish the discussion by looking at specific ways that divers can stay fit for diving, especially during the off season.

Now that we know what fitness is and have explored a large number of reasons why it is important for divers to be fit, are there specific exercises divers can do to be fit? The answer is of course yes. Any exercise is good but as we get older, training becomes more task specific. This means that to get the maximum benefit out of exercise, the exercise should match as closely as possible the activity you want to do. Therefore, our exercises should be as much like scuba diving as possible. Secondly, the 'kinds' of fitness we need depend upon the activity, so what kind of fitness do we need for diving? Diving tends to last for several hours (loading all the gear, getting to the dive site, doing the dive, getting back and unloading all the gear again). Therefore, diving requires a reasonable level of endurance (aerobic fitness). Diving also involves some pretty heavy lifting (tanks, weightbelt) and a reasonable amount of strength is required so we need both endurance and strength.

The best training for diving would be to dive every day! However, most of us will never be able to do that so we will have to improvise. Other than diving, the best single exercise is to swim lengths in a pool (in full gear) or at least mask, fins, snorkel and BC (inflated). The reason for the fins is so that you will strengthen your ankles and exercise the leg muscles in exactly the same way that you use them when diving. The reason for the BC is to increase your drag, again matching a real dive and making the swim harder and therefore better training. How long should you swim? The first 15 to 20 minutes of aerobic exercise allows the body to get into a steady-state of exercise and the best training takes place after the first 20 minutes. The longer the exercise period the better the training, but the amount of benefit per five minute period decreases as the exercise period gets longer. It seems to me that the optimum is to do aerobic exercise for 40 to 50 minutes straight, at least three times per week. Most of us will only get to the pool once per week so the other two times we will have to do another aerobic activity like running, biking, skiing, rowing, etc. This may seem like a lot but if you start slowly and work up to it you will be surprised how easy it can be. It is more important and safer to increase the 'duration' of your exercise period first and only increase the 'intensity' of the workout after you have got up to 40 or 50 minutes.

How important is this type of exercise? That depends upon your initial aerobic fitness level and the type of diving you do. It has been my experience that the average reasonably active person maintains a fairly good level of aerobic fitness up until they are around 30, assuming that they are not overweight. After age 30, even if the person looks good, unless they are specifically training to maintain their aerobic fitness, their fitness level will decline to the point where they might have trouble responding to a diving emergency. Certainly by age 35 or 40, everyone must specifically train with aerobic exercise to maintain an adequate fitness level.

Why am I emphasizing aerobic fitness so much? It is the single most important aspect of fitness. It is of prime importance in preventing high blood pressure, heart attacks, stokes and it is highly effective at "burning stress".

How hard should you exercise? The most important goal is to complete the full 40 to 50 minutes of exercise. If you are extremely tired or have been feeling unwell, back off the intensity of the exercise but do not back off the time. When you are feeling good, try to push yourself so that when the 40 or 50 minutes are up, you are almost completely spent.

How about strength? The amount of strength you need to dive safely depends upon the type of diving you do. Most people continue to become stronger until they are in their late 30s. Therefore, most divers will not have a problem with strength until they are older. If you are physically small, try to ensure that your tank and other gear is sized appropriately. If your dive buddy weighs 100 kg while you weigh only 50 kg, if they dive an 80 cubic foot tank, a 40 will probably give you the same dive duration. If you are finding it difficult to move your gear around or you are stiff and sore after diving, you need more strength training.

There are a large number of options and exactly what you should do depends upon both the muscle groups where you need more power and the types of equipment you have access to. Some authorities suggest the single best exercise is to put on your weightbelt, BC and tank and walk around the house every day. That is not a bad idea, just be careful not to fall!

The easiest and safest way to strength train is to join a gym and get a fitness trainer to design a program for you. One approach I like is to use a full range of resistance machines. The machines are each designed to work a specific muscle group and as long as the gym has the full line of equipment, two or three times around the circuit will give you an excellent general muscle workout. There are many different kinds of machines. Some use hydraulics to provide the resistance, some use springs or rubber bands, some use your own body weight and some have weights built into the machine. I do not believe that there is much to chose between them so what you use will depend primarily upon what you have access to. Just remember, it is important to keep the resistance down, especially initially, so that you do not hurt yourself.

When you exercise a muscle, you actually tear it down. The body then repairs the damage and makes it a bit stronger to try to withstand the next exercise period. This healing process takes two to five days, depending upon how much damage you did to the muscle during the training period. Therefore, NEVER do strength training on the same muscle two days in a row. If you are doing light to moderate strength training, you can workout three times a week with the same training program. If you get into heavy strength training, you should have several different training programs so that you only work some muscle groups one day, a different set of muscles the next time, and so on so that the muscles have enough time to heal before you work them again.

Other than resistance machines, strength training can be done with "free weights". This is when you have simple bar and dumb bells and put various amounts of weight on them. Training with free weights is highly effective and in some ways is better than using the machines as it is possible to work more muscle groups per exercise. The problem is that it is much easier to hurt yourself with free weights. I spent several years training and competing as an Olympic style (not caliber!) weightlifter and I love free weights. However, a number of years have passed and I do not find time to do strength training as often as I would like. When I do find the time, I frequently find that free weight training causes me a great deal of pain! It is very easy to overwork a muscle group, to stress a ligament or tendon to excess and it is quite difficult to put together a collection of exercises that will result in an all round strengthening program. It is also a lot more difficult to be continuously changing the weights on the bars. Therefore, unless you have been trained in how to lift free weights safely and unless you are very dedicated to weight training, I would suggest the resistance machines are a better way to go.

From the above comments, it should be obvious that I think home gyms are not a good investment. Most people are only able to buy one or two machines, either because of financial or space constraints. Therefore, they will never be able to get a complete workout. The only exception would be in the area of aerobic machines as you only need one. Running (treadmill) and rowing are the best as they work most muscles in the body. Bikes are slightly less effective as they work the arms less. I have not read any good studies on the "riders" (often advertised on TV) but they might be OK. The "walkers" might be easy on your knees but they also do not require much effort (I tried several times to get a good workout on one and couldn't). They are probably excellent if your initial level of fitness is very low. The step machines and climbers are good but a bit harder on your knees. The bottom line is that no one machine will give you both aerobic and strength fitness. Therefore, it might be OK to have one aerobic machine at home but you should still go to the gym for your strength training. It is possible to buy a complete set of resistance machines for home use but MUCH less expensive and more fun to join a gym!

The only other comment I must make on fitness training for diving involves the stomach muscles. Most divers have low back pain after a dive. The explanation is simple. The weightbelt and tank are usually over the low back and the diver tends to spend most of their time swimming in a horizontal position. The weight is trying to bend them in half, backwards, and the stomach muscles quickly fatigue and the strain goes to the back. The first step is to get the weight off the lower back. Wear ankle weights, get a BC that distributes the weight better, dive with steel tanks so that you do not need as much weight or lose the extra built in buoyancy (fat). It is sometimes possible to move some of the weight to your shoulders and off your waist. The second step is to make the stomach muscles stronger. This is much harder than it sounds and basically means "sit-ups", regularly, frequently and lots of them. Some guidelines on sit-ups. If you hook your feet under something, you will not be exercising your stomach but your legs when you sit-up. Therefore, never hook your feet. If your legs lift when you try to do a sit-up, it means that your stomach is too weak! Try extending your hands. In an extreme case, you might even have to hold a light weight in your hands to get up. Do several different kinds of sit-ups so that you work all of the abdominal muscles. Do "complete" sit-ups for the same reason, unless you find that full sit-ups cause you significant low back pain. In that case, do 1/2 sit-ups where you stop when your shoulderblades have lifted off the floor, then do twice as many!

If you have back or neck pain when you do sit-ups, the various abdominal machines can be excellent. Most of them are simply rounded bars with a pad for your head and places where you can place your hands. Your arms do not pull you up, they simply support your head so that your neck muscles do not have to work as hard. I have found that these machines are excellent but you have to do a lot of sit-ups to get the same training effect. This is the only other machine that I would suggest you might want to buy for use at home. Fortunately they are simple and not expensive.

At the start of every exercise period it is important to do a few stretches and warm-ups. However, the main stretching should take place at the end during the cool down period. All stretches should be done slowly and without a bounce.

That is about it for training for diving. Every diver will require a different training program but a few generalizations bear repeating. The single most important fitness type is aerobic training and it should be done at least THREE TIMES EVERY WEEK for 40 to 50 minutes. The most important strength training that all divers should do is to strengthen their abdominal muscles. Stomach exercises should be done EVERY DAY.

I hope that this discussion has helped you to understand a bit better what fitness is and how important it is that your fitness level be appropriate for your chosen activities. See you in the gym!