Athletics and cardiovascular health.

The heart includes systolic and diastolic components. The immediate effects of physical activity include increased sympathetic nervous and related hormonal activity; increased heart rate, contractility, stroke volume, and cardiac output. The time for systole and diastole are reduced, with relatively more work per beat. Light activity prior to the following strenuous exertion enhances performance, safety, and recovery. Children, women, and men show similar responses to activity: acute stress, with long-term improvements in cardiovsacular function. There is no cardiovascular reason for restricting activity for children or women. Mental and/or emotional stressors cause similar stress reactions, without the potential long-range benefits of regular physical activity. Athletics is viewed as an optional part of a lifetime of regular, vigorous activity, and as such can make a contribution to one's cardiovascular fitness. From this viewpoint, there is no need to put one in the stressful athletic situation until adequate pre-conditioning has taken place. Neither is there a place for inactive promoters of athletics for its own sake.