[Regulation of respiration during muscular exertion]

A brief critical review of literature shows that many authors still follow a classical theory that the respiration control is performed by feedback (by deviation of PCO2, PO2 and pH in blood). This point of view does not account for the exercise hyperpnea. The present paper contains the various data and considerations which show that respiration during muscular exercise is controlled by a combined self-learning system. The system is based on both disturbance (open-loop) control and feedback control. The signals of disturbance (of central origin and from receptors of exercising muscles) cause the increase of respiration during exercise. The signals of deviations (from peripheral and central chemoreceptors) correct the response of respiratory centre to disturbance signals. The self-learning takes place by the formation of conditioned reflexes that ensures the control of respiration (the stability of gaseous composition of blood during exercise).