By Bonnie Stein, M.Ed.
Amino acids are promoted in health food stores, the back of magazines, and in some gyms as necessary for greater athletic performance. Racewalkers, who wants to excel, might be curious as to whether they should try these products.
Amino acids are the building blocks of protein, similar to the way glucose makes up carbohydrates, and fatty acids make up fat. Amino acids are crucial for the synthesis (building and maintenance) of muscle tissue. Protein also is essential for growing hair and new skin tissue.
According to Page Love, a registered and licensed dietitian, and President of Nutri-Fit Consulting in Atlanta, some endurance racewalkers (20-50K distance competitors) may have an increased need for protein. She says that “endurance sports, especially very high intensity, long duration activities, decrease carbohydrate availability, thus forcing amino acid oxidation to increase which could possibly increase overall protein needs.”
Yet, Love says that even endurance racewalkers can meet their protein needs with a slight increase in the RDA, rather than supplementation. The RDA for protein is .8 grams per kilogram of body weight. Love recommends 1.2 - 1.5 grams per kilogram of body weight for endurance racewalkers.
When you take in extra amino acids or consume extra protein which your body can’t use, the excess is converted to fat for future use. The result is a weight gain comprised of fat, not muscle. Unfortunately, protein converted to fat can not be used as protein in the future. Once converted to fat, it remains as fat until it is utilized for fuel during aerobic exercise. Racewalkers who are not endurance athletes (less than 20K distance), will receive no benefit from an increase in protein intake, and may even gain weight as a result.
Additionally, excess amounts of amino acids can cause dehydration, gout, kidney problems, calcium loss and an increase in urea production. Substituting amino acid supplements for food may also result in suboptimal intakes of other nutrients such as iron, zinc, thiamin and niacin found in protein rich foods.
If single amino acids are consumed in large quantities, imbalances and toxicities of amino acids are possible. Long term risks are not conclusive; however, preliminary rat studies done recently at Cornell University and Washington State University have linked a high protein diet to an increased risk of cancer. Page Love Johnson cites a Tufts University Diet and Nutrition Letter which reported a case of psychosis and hallucinations resulting from single amino acid supplementation.
While protein is an important and necessary component of a healthy eating plan, most Americans already eat too much protein. It’s recommended by the American Dietetic Association that our protein intake be 10-15% of our daily caloric intake. That translates to about 50 grams for the average woman and 63 grams a day for the average man.
It is important to eat a small amount of protein with each meal. Good choices are lean meat, fish, or poultry. You can also choose non-fat or low fat dairy products such as skim milk, yogurt, or low-fat cheese. A premier protein food would be beans which are the only protein choice low in fat and high in fiber. No meat or milk products have any fiber.
For most racewalkers, amino acid supplements provide nothing more than an unnecessary expense. A better idea would be to maintain a healthy, balanced, low-fat eating plan and save your money for a new racewalking outfit.