FIGURE 5.

Outcomes of exercise on axon regeneration and functional recovery may differ for different kinds of axons and the treatment applied

A: in rats treated with 2 wk of daily moderate treadmill training, the amplitude of the direct muscle (M) response to stimulation of regenerated axons is increased markedly 8–10 wk after injury, whether the exercise was begun immediately (3 days after transection), delayed for 3 wk, or conducted using an upslope inclined treadmill. Mean amplitudes (±SE; n = 6 for each group) of M responses, scaled to the pre-transection M response amplitude (horizontal dashed line) are shown. B: similar data for the amplitude of the H reflex in these three groups. In animals of the immediate group, H-reflex amplitude is increased by exercise. In animals in the upslope group, the training actually decreases the amplitude of the H reflex. Some data are from Ref. 62, 63.