Courtesy of the Gatorade Sports Science Institute

Athletes spend millions of dollars annually on protein powders, protein bars, protein shakes, and numerous types of amino acid supplements, all with the belief that they need tremendous amounts of protein to use as fuel for exercise and to help build proteins in muscles. It is argued by the supplement manufacturers that only high-quality proteins can provide optimal muscle growth or that only amino acids are absorbed into the blood quickly enough to maximally stimulate protein buildup in muscles.

As is often the case in the dietary supplements industry, there is an ounce of truth and a ton of nonsense in these claims. Here are some facts about protein needs and protein supplements.

* Almost all the fuels used to provide energy for sports are carbohydrates and fats; proteins usually contribute only about 2% of the energy needed, and the maximal contribution of protein to energy in sport is likely to be less than 10%.

* It is true that athletes often need more protein in their diets than do inactive people. Except for a few athletes, the amount needed each day 1.2-1.6 grams of protein per kilogram of body weight (3-4 ounces of protein for a 160-pound athlete) is still very small. Moreover, this amount of protein can almost always be obtained from ordinary foods in the athletes normal diet, without resorting to expensive protein supplements.

* There are a few athletes, especially wrestlers, gymnasts, dancers, and others trying to lose weight or avoid weight gain, who may need to eat more protein to compensate for increased protein burning for energy. Still, the maximal amount of protein required for such athletes probably does not exceed 2.5 grams of protein per kilogram of body weight every day.

* It is true that the proteins in some foods, e.g., eggs, milk, and meat, provide a more complete mix of necessary amino acids than do the proteins in other foods such as those found in peas, corn, or wheat. The amino-acid quality scores for these proteins are sometimes stated as the biological value, the chemical score, the net protein utilization score, or the protein efficiency ratio. So, if all of the dietary protein for an athlete were to come from a single food source, it would be better to eat only eggs or milk or meat. However, this reliance on a single food source for protein would result in many other nutritional deficiencies. As long as an athlete chooses a variety of foods even if they are all from plant sources, there will be sufficient amounts of the required amino acids in the diet, and the quality of any given protein is of little consequence. Therefore, athletes who spend great sums of money on supplements of whey protein, for example, are unwise; they can get just as much amino acid incorporation into the proteins of their muscles by eating a variety of normal foods, none of which must necessarily include proteins of high quality.

* If you wish to gain muscle mass, you must consume extra food energy, in addition to enough protein. For example, if you want to gain one pound of muscle per week, you should consume an
additional 500 kcal of food each day. Otherwise, you will not achieve your goals, no matter howgreat a proportion of your food is protein.

So, how can you choose ordinary foods that are high in protein? You can check the nutrition labels on the foods you are considering to get a good idea of how much protein will be contained in each serving. For example, a 6 oz. can of tuna packed in spring water contains about 2.5 servings of tuna when drained of water. Each serving contains about 13 grams of protein, so by eating the entire can of tuna, an athlete could consume 13 x 2.5 = 32.5 grams of protein, nearly half the daily requirement for a high-school wrestler in the lower body weight classes. Similarly, 1/2 cup of canned black beans contains about 7 grams of protein, the same amount contained in 2 tablespoons of peanut butter.

Another way to help choose protein-rich foods is to study tables of food composition such as that included in this article. Other tables can be found in libraries, nutrition textbooks, cookbooks, and on the Internet. The U.S. Department of Agriculture (www.usda.gov) publishes on the Internet the USDA Nutrient Database for Standard Reference, perhaps the most complete such reference in existence. The particular table shown in this article is far from complete, but to make comparisons easier, the protein contents are listed per ounce of each food item. Some of the more protein-rich foods are highlighted in boldface, but don't ignore foods with less protein. Each of these foods can contribute to an overall nutritious diet. One drawback of this type of table is that no consideration is given to the volume of the food item that must be eaten to be equivalent to a weight of 1 oz. For example, the volume of an ounce of milk is very small compared to the volume of an ounce of puffed wheat cereal without milk.

In summary, most athletes can obtain all the protein that they need for optimal sport performance and muscular development from ordinary foods contained in their normal diets. There is no need to spend lots of money on protein supplements or amino acid supplements. As long as you consume enough calories and eat a wide variety of foods, the amino acid composition or quality of the proteins in the individual food itemsis of little or no consequence.