Relative Effects of Isokinetic and Plyometric Training on Vertical Jumping Performance

Forty-eight volunteer males were randomly assigned to one of three groups. Group I trained with isokinetic exercises, Group II trained with plyometric exercises, and Group III was the control. Subjects in the training groups trained three times per week for 8 weeks. The isokinetic group performed three sets of 10 repetitions per set of leg presses each training session. The plyometric group performed three sets of 10 repetitions per set of depth jumps from a height of 34 inches, with added resistance beginning with weeks 3, 5, and 7 of 10, 15, and 20 pounds, respectively. Prior to and at the end of the training period, all subjects were given a vertical jump-and-reach test. Covariance analysis was used to compare posttest scores with the effect of pretest differences removed. Results showed both training groups improved significantly in vertical jump capacity; however, no significant difference existed between training groups.