Strenuous exercise to which one is not accustomed can lead to muscle damage that is perceived as soreness in the afflicted muscles. Some evidence suggests that repeating a bout of exercise as much as...

Strenuous exercise to which one is not accustomed can lead to muscle damage that is perceived as soreness in the afflicted muscles. Some evidence suggests that repeating a bout of exercise as much as 2 or 3 weeks later, without any intervening exercise, causes less damage and, thus, less soreness. To examine this adaptation in more detail, Triffletti and coworkers* measured muscle soreness at 6, 18, and 24 hours after a bout of unaccustomed exercise in six subjects who each underwent four different bouts of exercise spaced 1 week apart (the data are in Table D-33, Appendix D). They hypothesized that there would be less muscle soreness after bouts 2, 3, or 4 than there was after bout 1. In addition, they hypothesized that the usual increase in soreness with time immediately following a bout of exercise would be attenuated after bouts 2, 3, or 4, compared to after the first bout. Is there any evidence to support these hypotheses? Perform the analysis using REML. Plot the model-derived means and standard errors of the means to help you interpret the findings.

Table D-33