The reactive agility skill and limb muscle power are necessary to support the athlete’s performance. This study aimed to test the validity of the interval training program content, with a difference in rest intervals of 60 s, 75 s, and 90 s. The research was verified by eight experts: three academic experts and five professional experts. This study was conducted on 30 junior table tennis athletes for six weeks with 18 meetings. The results showed that the combined interval training program of 60 s, 75 s, and 90 s of reactive agility and limb muscle power had quite adequate Aiken’s V validity because it exceeded the minimum standard of coefficient value of Aiken’s V = 0.75. The effectiveness test after being given a combination interval training program of 60 s, 75 s, and 90 s showed an influence on increasing reactive agility and strength of the athlete’s limb muscles. T-test showed Sig. 2-tailed reactive agility 60 s (0.024), 75 s (0.008), 90 s (0.007) and limb muscle power 60 s (0.001), 75 s (0.008) except on limb muscle power intervals of 90 s (0.246) because p > 0.05. This exercise program can be used as a training program to improve the reactive agility and muscle power of the limbs of table tennis athletes. For further research, there will be innovation in training programs related to reactive agility and leg muscle power in table tennis athletes.