The aim of this study is to determine whether concentric and eccentric isokinetic training performed at certain angular velocities in sedentary individuals is effective only in the angular velocities and contraction type where the training is performed, or at other angular velocities and contraction types that are not being trained. Twenty-eight sedentary in-dividuals (matched according to weight, age and gender) volunteered to participate in this case study. The study was conducted on a total of 56 extremities belonging to 28 individuals (14 women, 14 men) aged between 24 and 60 years. Concentric and eccentric strength tests were performed at 30-60-90-120-150-180°/sec. The participants were random-ly divided into two groups as concentric training group and eccentric training group, through stratified randomization matching. The training was done 3 days a week for a total of 6 weeks. At the end of the study, no difference was found between the pre and posttraining measurements in the concentric training group (P>0.05). In the eccentric training group, the eccentric muscle strength of the knee flexors and extensors at angular velocity of 90°/sec, the eccentric strength of the knee extensors at angular velocity of 120°/sec, and the eccentric muscle strength of the knee flexors at angular velocity of 180°/sec were found to be different and an increase was seen after the training (P=0.032, P=0.049, P=0.041, P=0.032). These results demonstrate that eccentric training may be preferred in cases where muscle strength increase is needed in short time.