Chronic training with static and dynamic exercise: cardiovascular adaptation, and response to exercise.

To determine the acute and chronic effects of static and dynamic exercise upon the cardiovascular system, two groups of athletes were studied and compared to untrained control individuals. Thus, 12 long distance runners (LDR) and 17 competitive weight lifters (CWL) were compared to 10 light controls (LC) and 14 heavy controls (HC). The echocardiographically measured left ventricular mass (LVM) was shown to be increased in both groups of athletes. When this mass was related to lean body mass, the LDR demonstrated a significantly increased LVM, whereas the CWL had a LVM similar to that of the HC. During static handgrip exercise, the LDR maintained a relative bradycardia and, consequently, a lower calculated double product when compared to the LC, whereas the CWL reacted similarly to the HC. Further, the LDR demonstrated higher end-diastolic and higher end-systolic volume indices than the LC during static exercise. The exercising stroke volume index and the cardiac index were, however, not significantly different in the LDR compared to the LC. In contrast to the LDR, the cardiovascular dynamics of the CWL changed in a manner very similar to that of the HC during static exercise. This information suggests, therefore, that endurance training alters both the absolute and relative left ventricular mass and the response of the cardiovascular system to static exercise. On the other hand, static exercise training increases the absolute but not the relative left ventricular mass. Also, the immediate hemodynamic response to static exercise is similar in athletes who train with this form of exercise compared to untrained control subjects.