Effect of Differential Pedal Rate on Ventilatory Indicators and Human Salivary Chromogranin A during Induced Locomotor Respiratory Coupling

Abstract

[Purpose] We studied the effect of the cycle ergometer pedal ratio calculated during locomotor respiratory coupling (LRC) on ventilatory indicators and salivary chromogranin A. [Subjects] Twenty-five subjects participated in our study. [Methods] The subjects were divided into 2 groups: one group performed pedaling at a rate of 50 rpm, and the other group performed pedaling at 40 rpm. First, the subjects pedaled at the anaerobic threshold (AT) under the spontaneous breathing condition for 10 min, and then performed the same exercise under LRC. [Results] The 50-rpm group showed persistent dyspnea under LRC; however, the 40-rpm group showed a significant decrease in the respiratory rate and dyspnea. Human salivary chromogranin A level was not related to coupling between pedaling and breathing. [Conclusion] Dyspnea decreased when the breathing rate during LRC was lesser than that during spontaneous breathing.