Relationship between postural control and respiratory movement during one-leg standing in healthy males.

[Purpose] The purpose of this study was to examine the relationship between postural control and respiratory movements after identifying the characteristics of respiratory movements in different postural holding tasks. [Participants and Methods] The total trajectory length was measured using a stabilometer (G-620; Anima Company, Tokyo, Japan), while respiratory movements were measured using an expiratory gas analyzer (PowerMetz; Anima Company, Tokyo, Japan) during closed-leg and one-leg standing. Respiratory movements were characterized as tidal volume (TV), respiratory rate (RR), minute volume (MV), and metabolic equivalents (METs). [Results] The total trajectory length, METs, RR, and MV were higher in one-leg standing than in closed-leg standing. The rate of change in the total trajectory length during one-leg standing was positively correlated with the rate of change in TV and negatively correlated with RR. [Conclusion] The results suggest that postural control of one-leg stance holding is associated with changes in respiratory motion.