ABSTRACT
ABSTRACT: The purpose of this study is to clarify the changes in muscle hardness by three treatments (stretching, hot pack and massage) that are commonly used to relieve muscle fatigue. Ten young male adults received the treatments in their anterior thigh. The thickness and hardness of the subcutaneous fat and the muscles in the anterior thigh were measured using an elasticity-measuring instrument with an ultrasound signal. In the stretching and hot pack conditions, an index of muscle hardness significantly decreased without change in muscle thickness, which indicates softening of the muscles. In contrast, the massage condition failed to show significant changes in the muscle hardness. These findings suggested that the stretching and warming of the muscles soften them, which might reflect relief of muscle fatigue.
