Circulating matrix metalloproteinase (MMP)-9 levels at rest and 2–75 min after exercise.

Data points indicate mean serum concentrations (± SEM) at the initial and final exercise sessions of a 6-week training intervention (n = 13). (A) Acute effects of resistance exercise (RE) and resistive vibration exercise (RVE); (B) Long-term effects: In both groups, MMP-9 levels were increased over resting levels 2–15 min after exercise. Significant differences from resting levels (time effect): ^‡‡P<0.01. There were no differences between initial and final exercises of the 6-week intervention in neither group.