B21 The influence of different breath patterns to the moment of buoyancy force around the center of mass : A preliminary report

Abstract

The purpose of this study was to examine if the escalation of leg-sinking effect of buoyancy around the center of mass (CM) during breathing changes due to different breathing patterns -- chest breathing and abdominal breathing. Five male participated in this study. The positions of the CM, the position of the center of volume (CV), and distance between CM and CV were determined. The results showed that CV-CM distance increased for 1.47cm with chest breathing and for 0.94cm with abdominal breathing. As a result of these change of distance, the leg-sinking effect increase for 10.27Nm with chest breathing and for 6.40Nm with abdominal breathing. The small leg-sinking effect decrease the energy cost of swimming. The results of this study indicates that abdominal breathing reduces the leg-sinking effect of buoyancy, suggesting that abdominal breathing may improve the performance of swimming.