Food, Water and Rest

Compared to other athletes, the dedication of swimmers is astounding. They often swim 10 miles per day, six days a week, 11 months a year. They invest more time and effort in trying to become better swimmers than in any other single activity of their lives except, hopefully, their schooling.

Sadly, many doom themselves to failure because they do not eat a proper diet, replace the fluids lost in training, nor get sufficient rest. Let me discuss each of these aspects of “training away from the pool”, starting with diet.

The food athletes eat ultimately provides the fuel for their training. Where food is concerned, the problem is usually one of insufficient quality, not quantity. Most swimmers ingest enough calories per day to replace the fuel they used in training. However, a large portion of those calories (perhaps 40 to 50%) consist of foods high in fat.

Junk foods, such as sweets, fried foods and meats loaded with fat form a large part of the typical American diet (and, increasingly, the diet of athletes from other nations). The problem with fatty food is that they are slow to digest and even slower to be stored in muscles as glycogen, the major source of food for training and competition. It typically requires 48 hours for fatty foods to be converted to glycogen and stored in the muscles.

Swimmers on high-fat diets easily ingest more calories for dinner on Monday, for example, than they use for training that afternoon. However, those calories will not replace the muscle glycogen that was used to fuel that training session until Wednesday, 1-3 workouts later.

The dilemma is obvious. Swimmers on a high fat diet can not replace their muscle glycogen supply between training sessions. Eating more food will not solve the problem. The swimmers gas tank (stomach) is full, but the fuel is not getting to the engine (muscles) between training sessions. Thus, the swimmer must turn to stored sources of fuel. One of these is fat. However, fat burns slowly and the athlete will not be able to train at speeds that are sufficient to produce the improvements in aerobic performance, anaerobic endurance and speed that are desired.

Another source of store fuel is muscle protein. When swimmers use this source, they literally “cannibalize” their own muscle tissue for energy and soon lose endurance and power.

"Cycling" is one method of dealing with this problem. Interspersing fast and slow swimming, pulling and kicking and changing strokes in training are ways to (1) reduce the rate of glycogen depletion, and (2) provide additional time for glycogen replacement between training sessions.

Another method is by replacing about half the daily quantities of fatty foods with foods that are high in carbohydrates. This change in the diet can shorten the muscle glycogen replacement time to 24 hours.

The advantage to swimmers are obvious. They will be able to train more intensely and more specifically for a greater number of sessions per week, and their dependence on muscle protein as a source of fuel will be reduced.

Good sources of carbohydrates are breads, cereals, pasta, noodles, pancakes, waffles, rice, potatoes, corn, beans and peas. Fruits and fruit juices are also high in carbohydrate content because the contain natural sources of sugar in the forms for fructose and glucose which are rapidly stored as glycogen in the muscles. Baked goods, soft drinks and candies (sweets) are not recommended even though they contain large amounts of sugar. They also contain large amounts of fat and very little else in the way of vitamins and minerals that are necessary for the prevention of training related dietary deficiencies.

The next topic concerns fluid intake. A common misconception is that swimmers, unlike athletes who train on land, do not need to drink water during training because they don't sweat. Swimmers also lose large amounts of body water when they train because they do sweat and because they spend more hours per day training than many other athletes. The fluid loss is not noticed because most of it evaporates before reaching the skin and does not appears on the body as sweat.

If you have ever weighed swimmers immediately before and after training, you will know that it is not uncommon for them to lose 2-3 pounds. Most of that weight loss is fluid.

Obviously, swimmers are not in the same danger of dehydrating as are runners. Nevertheless, water losses should be replaced as rapidly as possible. Better still, the fluid loss should have been prevented during the session in question so that plasma volume and, consequentially, circulation could maintained at optimal level.

Swimmers should be encouraged to drink a glass of fluid (approximately 6-8oz) every 30 to 45 minutes during training sessions so that the weight loss following training does not occur or is minimal. Plain water is an excellent and adequate source of fluid replacement. However, commercial preparations that contain electrolytes and glucose are also advantageous.

Lastly, we come to the topic of rest and sleep. It is unfortunate that we know so little about this important aspect of training. We know in vague terms that people replace their energy during periods of rest and sleep. We know very little about how this is done, however. We also know very little about the quantitative and qualitative aspects of rest and sleep – that is, how much at a time, how often and whether it should be inactive or active in some mild way (i.e. Walking, reading, meditating, etc.)

We know from experience that athletes do not train well when they are not getting enough sleep at night. Conversely, we have seen that athletes can tolerate much greater training loads when they have additional time to rest such as during vacation periods. The reason probably have something to do with the fact that periods of rest and sleep reduce daily “non-training” energy use, leaving more available for training. It may also be that muscle and central nervous system fuels, hormone levels and, “psychic energy” are replaced more rapidly when resting or sleeping.

It seems reasonable, to assume, therefore, that athletes will be able to tolerate greater training loads and, thus, reap greater training benefits when they are getting 6-8 hours of sleep per night. It also seems advisable that athletes rest at least one or two hours each day when their schedules permit.