The effect on o2 max of adding arm work to maximal leg work

Ten male subjects exercised maximally on a bicycle ergometer with legs alone and with arm work combined with maximal leg work. V̇o2 max was 10% higher with combined work than with legs-only work (p < .002). This result demonstrates that V̇o2 max is a function of the mass of muscle engaged in the exercise. It also casts considerable doubt on the hypothesis that V̇o2 max is limited by the ability of the heart to pump blood.