Neurogenic factors affecting ventilatory and circulatory responses to static and dynamic exercise in man.

The possible influence of neurogenic factors on respiratory and circulatory responses to continuous static (CSE), rhythmic static (RSE), and dynamic (DE) exercises was studied in 15 healthy young men. Ventilation (VE), oxygen uptake (VO2), cardiac output (Q), and blood pressure (BP) were measured during the steady-state of the exercise. For a given VO2, VE, and respiratory frequency (f) enhanced significantly with increasing frequency of RSE, and for the same frequency, the responses of these variables to RSE were significantly higher than those for DE. Although a similar trend was observed in heart rate (HR) and Q responses to exercises, it was not as strong as for ventilatory responses. These results lead to the conclusion that ventilation and circulation during exercise may be influenced by some neurogenic factors mediated either centrally or peripherally.