Figure 1. Differences in fatigability between young and old adults.

A, average torque exerted by young and old adults during five sets of 30 maximal lengthening contractions with the dorsiflexor muscles. Each data point indicates the mean ± s.e.m. of five successive contractions for 16 subjects in each group. Adapted with permission from Baudry et al. (2007). B, each data point denotes the time to failure for the one young man and one old man who were matched for strength. The task was to sustain an isometric contraction with the elbow flexor muscles at 20% of maximum for as long as possible. The time to failure was longer for the older man of each pair. Adapted from Hunter et al. (2005).