Figure 2From: The influence of a CYP1A2 polymorphism on the ergogenic effects of caffeine40-km time in both the placebo condition (y-axis) and the caffeinated condition (x-axis) for both AA homozygotes and C allele carriers. The line of identity is plotted and reflects no difference between the two trials. Data points above the line of identity reflect an improved 40-km time in the caffeinated condition.Back to article page