Practical Health Advice: Nutritional Requirements of Body Builders

Few athletes are as diet-conscious as bodybuilders, and there's a simple reason why. While athletes such as wrestlers, gymnasts and boxers need to be concerned with maintaining a specific bodyweight range, bodybuilders literally use food to alter body composition.

Consequently, the training and dietary practices of bodybuilders are a continuing source of fascination for many sports scientists and dieticians. A new review of the nutritional practices of bodybuilders that was published in a 1995 edition of the Journal of Strength and Conditioning Research exemplifies this interest. It features a detailed analysis of past studies involving the dietary habits of bodybuilders. One limitation of such studies, however, is that they often make conclusions based on a limited sample population.

For example, judging by their responses, the bodybuilders surveyed in most studies don't have an abundance of nutritional savvy. A few studies found that precontest diets were lacking in essential nutrients. This is to be expected considering the restricted calorie intake and lack of variety typical such diets. Minerals were an especially vexing problem, with most female bodybuilders showing deficient calcium intakes. Apparently they weren't aware that they could solve the problem simply by taking supplements.

As dieticians are wont to repeat ad nauseam, the purpose of food supplements is to supplement what may be missing in your diet. Janet Walberg-Rankin of the Department of Nutrition at Virginia Polytechnic Institute and State University, the author of this review, says that women bodybuilders are obsessed with food and are more likely to resort to laxatives than women who are not involved in weight training.

This position is counter to those of other researchers, who report that female bodybuilders are less obsessed with both food and weight management because of a feeling of empowerment they get from bodybuilding. Bodybuilders habitually consume large amounts of protein in the belief that high protein intake promotes positive nitrogen retention in the body that's conducive to muscular growth. While the research on this is equivocal, most studies seem to indicate that bodybuilders do indeed have an increased need for protein.

The controversy arises as to precisely how much protein fosters muscular growth or recovery. Based on past studies examining this question, Walberg-Bankin suggests a range of 1.2 to 2.0 grams per kilogram of bodyweight daily. Since protein needs bear a direct relation to calorie intake, it would be more prudent to shoot for the higher range of protein when dieting. The author believes that the stringent lowfat diets commonly followed by competitive bodybuilders are needlessly restrictive. To underscore her point, she cites a study that involved a group of women who followed 1 200-calorie-a-day diets for 10 weeks. The only variable in the diets was fat content, which was either 10, 35 or 45 percent. At the end of the study the women showed no differences in weight loss despite the amount of fat taken in.

Walberg-Rankin feels that in an effort to cut fat out of their diets, bodybuilders reduce the variety of foods they eat, which in turn promotes nutrient deficits. In the real world, however, nutritionally sophisticated bodybuilders are fully aware of the unbalanced aspects of a limited precontest fare and correct the problem by using food supplements, often extensively. Again, this is the real advantage of quality food supplements-to supply essential nutrients at minimal calorie or fat cost.

Another problem bodybuilders, particularly those preparing for a contest, face is dehydration. In an effort to achieve the coveted ripped appearance that elicits both audience attention and, in pro events, money, many bodybuilders teeter dangerously close to pathological dehydration, which is characterized by muscle cramps, fatigue and possibly fainting.

Walberg-Ranldn mentions the sad, untimely death of pro bodybuilder Mohammed Benaziza, who died shortly after winning a European pro contest. While she says that both dehydration and extreme fluid restriction contributed to Benaziza's death, other substances may also have been involved. Nonetheless, overly restricting fluid intake shortly before a contest can indeed prove disastrous. This is especially true if it's combined with diuretics prescribed by the latest self-styled 'guru," who probably doesn't have the medical knowledge to deal with common side effects. Walberg-Rankin gives a thumbs- down to amino acid supplements that are purported to increase growth hormone release. She notes that studies examining the effects of such supplements on bodybuilders found little or no effect.

To her credit, the author says that carbohydrates are more critical to endurance athletes than they are to bodybuilders, and she suggests that they should comprise at least 60 percent of a bodybuilder's cabries-the quantity needed to replenish muscle glycogen, the primary fuel for bodybuilding workouts. She also alludes to a trick mentioned in this column in the past. Consuming liquid carbohydrate drinks while training works particularly well when you're restricting calories or carbohydrates. Since you burn about one gram of carb per minute of exercise, most of the carbs ingested during a workout are used as energy Any left over just give you a head start toward replenishing depleted glycogen stores. In other words, you get a needed energy boost that helps bolster training intensity while not overly inhibiting fat loss.

Based on her survey of available data, Walberg-ltankin suggests that instead of following a typical 6 percent fat diet, bodybuilders would be well advised to increase their fat to 15 to 2D percent. She adds that overly restricting calories leads to muscle catabolism and advises a precontest calorie range of 2,500 to 3,000 for men and 1,200 to 1,700 for women, depending on activity level, body composition and resting metabolic rate.