Fig. 1From: Caffeine supplementation is ergogenic in soccer players independent of cardiorespiratory or neuromuscular fitness levelsMeans and SD of time to exhaustion with caffeine (solid bars) and placebo (hatched bars). Participants were divided according to cardiorespiratory (left) or neuromuscular fitness (right), with high groups shown in black and medium groups shown in grey. There was a significant treatment effect (p < 0.001)Back to article page