Hemodynamic response to work with different muscle groups, sitting and supine.

Abstract

Submaximal and maximal work was performed on bicycle ergometers with arms, with legs, and with arms and legs, in sitting and supine position, respectively. Six male and 4 female healthy and well-trained subjects were studied. During maximal exercise with arms, maximal V02 [O2 consumption] and cardiac output (dye-dilution technique) were 66 and 80%, respectively, of the values attained in sitting maximal leg work. Simultaneous work with arms and legs did not allow higher V02 or Q than maximal work with legs in sitting position. At a given submaximal V02, heart rate, intra-arterial blood pressure, and pulmonary ventilation were the same in leg exercise as in combined work, but the values were significantly higher during arm work. Stroke volume (in both positions) was higher during exercise then while resting; the lowest exercise values were registered during arm work in sitting position and the highest during combined work, supine position. Calculated total peripheral resistance was higher during arm work compared with other types of work at corresponding levels of O2 uptake.