THE EFFECTS OF REPEATED MAXIMAL ISOKINETIC ECCENTRIC EXERCISE ON TOTAL WORK AND ISOMETRIC FORCE

622 This study investigated the effects of repeated maximal isokinetic voluntary eccentric exercise (MAX) on total work and maximal isometric force(MIF). Twenty-four healthy, active males (22.9 ± 2.3 yrs, 173.6± 6.9 cm, 68.2 ± 5.1 kg), served as subjects. Subjects were randomly assigned into a control group (n=12) and an exercise group (n=12). The initial exercise (MAX1) was 3 × 10 reps of MAX on the non-dominant elbow flexors with Cybex 6000 at a speed of 60 ° /sec. The exercise group performed the same exercise 3 days (MAX3) and 6 days (MAX6) after MAX1. MIF was measured before and after each eccentric exercise (MAX1, MAX3, and MAX6) as well as 9 days after MAX1. The MIF of the control group was assessed prior to and immediately, 3, 6, as well as 9 days after MAX1. No significant differences in MIF were found between the two groups. There was a significant drop in total work through 3 exercises (MAX1=2409 J, MAX3=1508 J, MAX6=1819 J) for the exercise group. Moreover, the MIF decreased 43%, 22%, and 28% immediately after MAX1, MAX3, and MAX6, respectively. These decreased values were positively correlated with total work performed (r=0.85). Conclusions: 1. Repeated maximal eccentric exercise during DOMS was only 63% and 76% of the initial total work. This information may serve as a reference for coaches who must prescribe a training load for athletes during DOMS. 2. There was a direct positive correlation between the amount of total work and the strength decrement measured immediately after exercise. Therefore, too much intense exercise before competition may negatively effect performance.