Central Command to Suppress the Instability of Locomotor-Respiratory Rhythm Coupling at Running

Abstract

It is known that a phenomenon in which a respiratory rhythm coupling with a locomotor rhythm (LRC: locomotor-respiratory rhythm coupling) occurs during running. At this LRC, the respiratory rhythm rate increases in proportion to the locomotor rhythm intensity, and when it approaches the limit locomotor rhythm intensity, an unstable phenomenon of the respiratory rhythm increases becomes sometimes observed. This instability of the respiratory rhythm causes lower exercise efficiency, so it is necessary to keep the stable respiratory rhythm up to the faster locomotor rhythm as far as possible. Therefore, we obtain a model with a locomotor rhythm added to the nonlinear differential equation that expresses the respiratory rhythm. We consider a method of a central command to suppress the instability of the LRC for this model. By simulation, we show LRC, the instability of the LRC, and the central command to suppress this instability.