抄録
It is well known that exercise may cause stiffness of muscles by the study with questionnaire or palpation. However the reports concerned with objective measurement of muscle stiffness are a few. We already reported that the soleus muscle hardness raised after exercise loading and gradually lowered to the initial level using newly devised muscle hardness meter in healthy human volunteers. This devise has three foots. Both side-foots are fixed, a center foot is movable and 6.3mm longer than both side-foots. When both side-foots touch the skin surface covering the object muscle, the pushed back length of center foot indicates the muscle hardness. If the muscle were harder, push backed length would be longer. Stretching is well known to soften muscles, however the reports concerned with objective measurement of stretching effects are also a few. We reported that stretching in state with knee extension accelerated the restoration of soleus muscle hardness after exercise loading, but did not affect exercise-unloaded muscle hardness objectively. We investigate the effect of stretching in state with knee flexion on exercise-unladed soleus muscle in the present study. The stretching in state with knee flexion lowered the hardness of exercise-unloaded soleus muscle with statistical significance (p=0.009) by analysis of variance. These results indicate that the stretching in state with knee flexion may be more effective on the soleus muscle hardness than in state with knee extension in human. Furthermore the usefulness of newly devised muscle hardness meter was indicated. [J Physiol Sci. 2008;58 Suppl:S68]
