Ventilation and acid-base equilibrium for upper body and lower body exercise.

The purpose of this study was to compare pulmonary ventilation and blood acid-base responses for upper and lower body exercise at a variety of metabolic intensities. Nine male subjects completed a progressive intensity, discontinuous test for arm crank (AC) and cycle (CY) ergometry. During submaximal exercise, oxygen uptake (VO2), pulmonary ventilation (VE), VE/VO2, alveolar ventilation (VA) and blood lactate (LA) values were found to increase, whereas arterial carbon dioxide partial pressure (PCO2) and arterial pH values were found to decrease with increasing power output for both modes of ergometry. Generally, for a given submaximal power output level, VO2, VE, VE/VO2, VA. and LA values were higher, but, PCO2 and pH values were lower for AC compared to CY exercise. During maximal exercise, VO2, VE, VA, LA, and PCO2 values were lower for AC than CY exercise. When VE, VA, LA, PCO2 and pH were expressed in relation to percent of peak VO2 (ergometer specific), nearly identical response patterns were found for both modes of exercise. These results indicate that pulmonary ventilation and blood acid-base responses are dependent upon relative exercise intensity rather than the muscle groups employed.