Eight experienced oarsmen and five inexperienced subjects performed a multi-stage exercise test on a rowing and bicycle ergometer. Oxygen uptake, heart rate and minute ventilation were observed on both exercise modes from light to maximal exercise. Although the o2max values were slightly higher on the bicycle ergometer ( 6.0% and 4.0% for the oarsmen and inexperienced subjects) differences were not significant (P>0.01), nor consistent in all subjects. Max heart rates and lactate levels were similar on both exercise modes. The VE/Vo2ratio, however, was consistently higher on the bicycle than on the. rowing ergometer at maximal exercise for all subjects (7.2% and82%for the oarsmen and inexperienced subjects, (P< 0.01). Apparently, the development of Vo2max on the bicycle ergometer was characterized‘ by a larger VE/Vo2when compared with the rowing ergometer. The cramped position of the body while rowing appears to constrict the abdominal muscles, which may limit their ability to aid in the expiratory phase of the breathing cycle. The forcing up of the abdominal viscera in this position may also constrict the action of the diaphragm during inspiration.