Cardiovascular and pulmonary responses to exercise

Abstract

Voluntary contraction of skeletal muscle increases the demand for oxygen and fuels such as glycogen and fatty acids. Whereas fuels are conveniently stored within muscle cells close to the mitochondria and contractile machinery, there is practically no oxygen reserve in muscle cells and the small amount found in the blood can sustain resting aerobic metabolism only for a few minutes. When muscles contract, they need more oxygen, and whole body oxygen consumption can increase by 10-to 20-fold. The circulatory and the pulmonary systems work together to increase oxygen transport in a highly responsive and coordinated manner. By performing specific exercises consistently for weeks, months, or years, an athlete can stimulate the cardiovascular system to adapt specifically to them. Presented in this chapter is a discussion of the cardiopulmonary responses to a single exercise bout, called the acute response to exercise, as well as chronic adaptations of the cardiovascular system to the many different demands of sport. © 2008 Humana Press.