[Objective] We examined the laterality of the lower limb muscles during sports activities. [Subjects] Our subjects were 44 members of a high school baseball club (mean age: 16.6±0.5). [Method] We measured the strength of the subjects' quadriceps femoris muscle and toe grip and compared the muscle strength of the dominant leg (the leg used to kick a ball) with that of the nondominant leg, as well as the muscle strength of the supporting leg (the take-off leg in long jumps) and that of the non-supporting leg. During a batting action, we defined the leg closer to the catcher as the pivoting leg and the one closer to the pitcher as the stepping leg, and compared their muscle strength. [Results] With regard to muscle strength of the dominant and non-dominant legs, as well the supporting and non-supporting legs, we did not observe significant differences in the strength of either the subjects' quadriceps femoris muscle or toe grip. On the other hand, in the batting action, the toe grip strength of the pivoting leg was significantly stronger than that of the stepping leg. We did not observe significant differences in the quadriceps femoris muscle strength. [Conclusion] Our results suggest laterality of the lower limbs during a batting action, namely the pivoting leg's stronger toe grip strength compared to that of the stepping leg.
