Metabolic responses and performance in tennis after caffeine ingestion

Controversy still exists concerning the potential ergogenic benefit of caffeine. A decreased glycogen depletion due to an increased lipolysis and lipid oxidation, an enhancement of neuromuscular function and an optimisation of central nervous system function has been discussed (Powers and Dodd, 1985; Jacobson and Kulling, 1989). In some cases increases in aerobic (Ivy et al., 1979) and anaerobic endurance (Anselme et al., 1992) were found after caffeine ingestion. Nevertheless, several studies have failed to exhibit a beneficial effect (Butts and Crowell, 1985; Powers et al., 1983).