The effects of stimulating Neiguan acupoints on cardiac pump function were studied in 20 athletic subjects during the performance of submaximal (70% VO₂max) stable bicycle exercise in the supine position. M mode, two dimensional echocardiography and a computerized light-pen system were used to quantitatively assess the differences between stimulating and not stimulating Neiguan acupoints. Measurements were taken with the subjects at rest, every 12 minutes during exercise, and after exercise. Results indicate that stimulating Neiguan acupoints improves cardiac pump function during exercise and accelerates the recovery of heart function after exercise.