In a sport event competition, power is one of the essential elements to achieve a maximum performance. Exercises conducted to increasethe leg power must also be aimed in the leg muscles in particular. In the mid-teens is very precise in the development of basic skills in sports. To determine the effect of jump squats exercise to increased the power of leg muscles, to determine the effect of core stability exercise in jump squats to increased the power of leg muscles, to determine differences in the effects of squat jump exercise and increased core stability exercise in jump squats to increase the leg muscles power. This research is a quasi experimental study design with pre-test and post-test. sample of 30 students. Jump squat exercises and core stability given to respondents 3 times in 1 week. Measurement instruments used were standing board jump. This study used a measuring tool in the form of leg muscle power Standing Board Jump. Based on statistical test paired sample t-test showed the effect of squat jump with significant value 0.000 0.05 (p). There is the influence of squats jump to the increased power limb muscles, there is the effect of increased exercise core stability in squats jump to the increased power of leg muscle and There is a difference of influence, where the addition of exercise core stability in squats jump better than just training methods squat jump to increased leg muscle power
