Effects of increased muscle tone in different body regions on response movements during Kendo

Abstract

The goal of the study was to investigate the effects of muscle tone in different body regions, especially the right arm and abdomen, on response movements of Kendo fighters. A survey was conducted to identify the muscle regions in which Kendo fighters felt tension associated with good or poor movement. Based on these findings, three experiments were performed to investigate the influence of muscle tone in different body regions on response movements when the facemask was hit with a bamboo sword. Using a high-speed camera, three parameters were measured: reaction time (the time from presentation of a stimulus to the start of movement), action time (from the start of movement to completion), and response time (the sum of the reaction and action times). The results showed that (1) tension of the muscle in the right arm was associated with poor movement, whereas abdominal tension was associated with good movement; (2) muscle tone in the right arm delayed the response movement due to slow reaction times; (3) achievement of an appropriate abdominal tension using abdominal training practice changed the posture by lowering the position of the abdomen; and (4) abdominal training practice quickened both the response time and the action time compared with hitting practice. These results suggest that instruction to increase abdominal muscle tone may be an effective strategy to increase the speed of response movements.