Fig. 2

Maximal fat oxidation (MFO) in the morning, and in the afternoon, after ingestion of caffeine or the placebo. Panel a: Individual observations for each subject (grey lines), and the mean for all subjects (black line). Panel b: Individual observations for each subject (black dots), standard deviation and minimum/maximum values (box-and-whisker plots), and the P value obtained by two-way ANOVA. Similar letters (i.e. a-a; b-b, etc.) indicate significant post hoc differences