Evaluation of Influence on Walking using Load-controlled Treadmill of Single-belt and Split-belt

Abstract

Currently, elderly people account for more than 25% of the population in Japan. Hence, Locomotive syndrome accompanying aging is a problem Japan faces. Locomotive syndrome is a condition in which walking motion becomes difficult due to aging. This research is focused on Sarcopenia, which is one of the causes for Locomotive syndrome. Sarcopenia is the decline of general muscle strength due to aging or disease. To prevent sarcopenia, it is necessary to give effective stimulation and load to antigravity muscles. We developed a self-paced “Load-controlled Treadmill” with a single-belt and two built-in force plates which strengthen the soleus muscles, which is a one of antigravity muscles. In this paper, we investigated the difference between single-belt treadmills and split-belt treadmills. Two subjects attached motion capture systems and shoes to measure reaction force. They walked 30s with constant load r = 0, 10, 20, 30[N] on both treadmills. Result showed that the angular range of motion of ankle joints when walking on single-belt treadmills was up to 2.7 times larger than when walking on sprit-belt treadmills. This result suggests that people can efficiently perform both efferent and afferent contractions of soleus and gastrocnemius muscles on single-belt treadmills walking. Force reading showed that the ankle joint moment when walking on single-belt is larger during terminal stance phase. Suggested that kicking force is stronger and muscle activity is greater when walking on single-belt treadmills perhaps. The results, as a whole, suggest that single-belt treadmills better simulates actual walking.