The aim of this study was to examine the impact of leg muscle strength and leg muscle explosive power on Tarung Derajat side kick ability through reaction speed. This study enhances the existing literature regarding the effect of leg muscle strength and leg muscle power on the side-kick ability of Tarung Derajat and includes reaction speed (simple and total), which is often trained to determine the level of performance in martial arts. In this study, subjects were randomly assigned n = 60 people to the test to see the ability of each of the proposed variables. Next, to examine the model structure effect of this study, we made use of IBM SPSS software. The results showed that leg muscle strength, leg muscle explosive power, and reaction speed had a significant impact on the ability of the Tarung Derajat side kick both directly, indirectly and totally. These results illustrate the important role of the direct influence of the yield power of the leg muscles which have a major influence on the side kick abilities of Tarung Derajat athletes. The implications for practitioners and researchers are discussed in detail.