Fig. 5. Length-dependent effects of eccentric exercise and post-tetanic potentiation (PTP) on the 60:200 Hz force ratio. (A) 60:200 Hz force ratios before (pre-exercise, closed symbols) and 80 min after (post-exercise, open symbols) eccentric exercise. The ratios were calculated for the non-potentiated (circles) as well as for the potentiated (triangles) condition (mean ± S.E.M). Exercise decreased the 60:200 Hz force ratio whereas PTP increased the 60:200 Hz force ratio significantly at most muscle lengths. (B) Post-exercise 60:200 Hz force ratios expressed as a percentage of the pre-exercise ratios at different muscle lengths (circles: non-potentiated condition, triangles: potentiated condition). Significantly less LFF was present in the potentiated condition than in the non-potentiated condition at most muscle lengths. ^*Significant difference between non-potentiated and potentiated condition.