In recent years, there has been a proliferation of technology and sport science utilized within an athlete’s physical activity and exercise. This study aims to assess the effectiveness of two strength and conditioning exercises, namely, a customized free-weight exercise and plate-loaded machine exercise, on the lower limb muscle activities of the amateur high jumpers. Six amateur high jumpers were divided into two groups, a customized free-weight group and plate-loaded machine group (control group) and performed exercises as instructed by the coach. The EMG signal of the Rectus Femoris and Bicep Femoris muscles were recorded during the exercises. Metronome was used to control the speed of the exercise and it was standardized for all subjects. The harmstring’s cable pull exercise (customized free-weight) triggered Bicep Femoris more compared to the leg curl exercise (plate-loaded exercise). Similarly, in the case of Rectus Femoris muscle, the front squat exercise (customized free-weight exercise) triggered higher muscular activities compared to the leg extension exercise (plate-loaded exercise). In conclusion, the customized free-weight exercise has indicated higher muscle activities compared to the plate-loaded exercise.