Aging, Respiratory Function, and Exercise

Abstract

Aging leads to a progressive deterioration of lung function, including a decrease of vital capacity, an increase of residual volume, a tendency for the airways to collapse during expiration, enlargement of all components of the respiratory dead space, a poor mixing of inspired gas, poor matching of ventilation with perfusion, a decrease of pulmonary diffusing capacity, and a substantial increase in the work of breathing. Ventilatory demand is increased during most physical tasks, but arterial blood homeostasis is surprisingly well maintained when elderly persons undertake vigorous exercise because peak cardiac output declines in parallel with the loss of ventilatory function. However, dyspnea progressively restricts peak effort as one ages. The exercise specialist cannot restore aged or damaged pulmonary tissue but can attempt to reduce the rate of future functional loss by encouraging smoking cessation, avoiding air pollution, and controlling acute infections. Enhanced fitness, stronger skeletal muscles, and better coordination can reduce ventilatory demand. Resisted breathing exercises may also strengthen the chest muscles and allow a mechanically more efficient pattern of breathing.