Previous investigations have shown the benefits of aerobic dance and bench step training programs. Their main focus has been to examine cardiovascular improvements and caloric expenditure during these activities. Therefore, the purpose of this study was to examine the effects of exercise mode on isokinetic strength, power, and endurance of the quadriceps. Twenty-nine non-smoking, free from history of knee pathology, non-physically active females (20.6 ± 2.8 years, 160.6 ± 4.9 cm, 61.9 ± 16.5 kg) volunteered for this investigation. Non-randomized testing procedures were performed due to the nature of the study. Of the 29 subjects, there were n=11 in the step Aerobic (SA) group, n=8 in the High Impact (HI) group, and n=10 in the Control (CT) group. Subjects were tested twice for quadriceps muscle function utilizing the following isokinetic tests: Peak Torque (PT) , Peak Torque to Body Weight Ratio (PTBW), Average Power (AVP) , and Endurance Ratio (END) on the Cybex 11+ isokinetic machine before and after the 12-weeks of exercise training. / Master of Science