Amino acids are used in the body to make proteins, which are essential to help build and repair muscles. Amino acids and other types of sports supplementation products are commonly used by athletes to help enhance athletic performance. Athletes do require more protein than non-athletes. However, some studies show that amino acid supplementation is not necessary to improve your running performance.
Protein and amino acid supplements are best utilized by the body, especially in athletes, if they contain all essential amino acids. Essential amino acids are those the body cannot make but need to help build proteins. Therefore, essential amino acids must be obtained through your diet or supplements. Examples of complete proteins that contain all essential amino acids are whey, casein and soy.
Although Medline Plus notes that most Americans eat twice as much protein as they require, amino acids can help runners meet their daily protein requirements if they don’t consume enough protein from foods alone. The American Dietetic Association recommends 1.2 to 1.4 grams of protein per kilogram of body weight per day for endurance athletes and 1.2 to 1.7 grams of protein per kilogram of body weight per day for strength athletes, which is equivalent to about 0.5 to 0.6 grams of protein per pound of body weight per day for endurance runners.
A study published in a 2011 edition of the “Journal of the International Society of Sports Nutrition” found that short-term amino acid supplementation does not affect skeletal muscle damage, muscle soreness or athletic performance in male 100 kilometer ultra-endurance marathon runners. In this study the amino acid supplements were given to the runners before and during the 100 kilometer race.
Another 2009 study in the “Journal of Sports Medicine and Physical Fitness" found that long-distance male and female runners participating in a three-day intensive training program who consumed branched-chain amino acid supplements reported a reduced sensation of muscle fatigue and soreness. However, one limitation of this study was it used only 12 subjects.
Although studies about amino acid supplementation in athletes show mixed results, the American Dietetic Association reports that protein and amino acid supplementation has not been shown to enhance athletic performance, but when consumed in close proximity to endurance or strength exercises, it may benefit the maintenance, synthesis and repair of skeletal muscle in response to training. Medline Plus notes that amino acid supplementation or high-protein diets are not recommended to enhance athletic performance.