
Similar to creatine, muscle contains significant quantities of a substance called carnosine.
Carnosine is a very important buffer in muscle, meaning that it helps to maintain a normal balance of acidity. Fatigue during high-intensity exercise such as sprinting and weight lifting is linked to acid (hydrogen ion) build up in the muscles and blood.
This is the so-called burning sensation you feel at the end of a hard bout of exercise. Muscles reduce their work capacity when acid levels get too high. Therefore, increasing
carnosine may delay fatigue and increase performance. Carnosine is made from two amino acids: L-histidine and beta-alanine. Beta-alanine is made by our bodies and obtained in the diet. The reason it may be more important than previously thought, is that it is rate-limiting in the synthesis of
carnosine levels in muscle. Research continues to shed light on how this supplement may help athletes. Take for example a recent study performed in collegiate wrestlers and football players. These athletes were supplemented with 4 grams per day of beta-alanine or placebo for 8 weeks. Compared to placebo, the beta-alanine group did better on a battery of performance tests. Wrestlers lost weight whereas football players gained weight over the 8 weeks, but in both athletes beta-alanine resulted in significant increases in lean body mass. How beta-alanine improves body composition and performance remains unclear, but given the positive effects in the laboratory as shown in this study and many others it is reasonable to assume they may translate to the playing field.
. Kern BD, Robinson TL. Effects of β-Alanine Supplementation on Performance and Body Composition in Collegiate Wrestlers and Football Players. J Strength Cond Res. 2011 Jun 8.