Infographic. A systematic review and meta-analysis of the effect of ?-alanine supplementation on exercise capacity and performance.

Carnosine (?-alanyl-L-histidine) is an abundant compound in skeletal muscle, suggesting it plays an important role during exercise, with a key physiological role considered to be intracellular pH regulation. Chronic ?-alanine supplementation can increase muscle carnosine content when taken for several weeks, and studies have shown that supplementation between 4 and 24 weeks can improve high-intensity exercise capacity, with the gains in exercise associated with the increase in muscle carnosine content. Although several studies have demonstrated the efficacy of ?-alanine supplementation as an ergogenic aid, there are a number of confounding factors that may modify its effect, including exercise type, duration and mode, training status and cosupplementation, which may influence the effects of ?-alanine supplementation. The aim of our systematic review and meta-analysis was to determine the effects of ?-alanine supplementation accounting for these potential modifying factors