Cardiac Function Tests as Indexes of Fitness

Abstract

Ventricular function measurements such as the Tension Period (TP) and the Q to First Heart Sound Interval (Q-1HSI) have received increasing attention as possible simple indexes of a person's cardiovascular fitness. In order to evaluate the usefulness of these tests for measuring fitness, they were compared with fitness scores obtained using a standard fitness test. The fitness score (Physical Work Capacity-150) of 31 male subjects was determined and correlated with their TP and Q-1HSI measurements taken at rest. The results showed little correlation between the PWC-150 and the TP (r = .21) or between the PWC-150 and the Q-1HSI (R = .13). The resting heart rate actually showed a closer correlation with Physical Work Capacity (r = –.53) than did either of the ventricular function measurements. Thus, from the results obtained in this study, cardiac function tests do not appear to offer a good substitute for the more strenuous tests of cardiovascular fitness.