Physiological effects of active and passive exercise

¹ Life Sciences and Space Environment Laboratory, Republic Aviation Corporation, Farmingdale, Long Island, New York

A comparison of the physiological effects of active and passive exercise was accomplished using two methods. In the first series of experiments, the exercise was held constant. In the second method, an attempt to match oxygen consumption was employed. The results, evaluated in view of preceding investigations in the same area, indicate that: 1) Passive exercise inincreases ventilation in excess of the metabolic need. The greater ventilation increases the ventilating equivalent and lowers the end-tidal Pco₂, possibly causing respiratory alkalemia. 2) The increase in ventilation accompanying passive exercise does not produce a corresponding increase in heart rate. 3) Passive exercise increases heat production beyond the level indicated by oxygen consumption. These findings support the concept of a temperature factor being involved in the hyperventilation of exercise.

Submitted on March 25, 1964