Abstract
The effect of submaximal arm, leg, and“arm+leg”exercise on oxygen uptake (VO2), heart rate (HR), and pulmonary ventilation (VE) was studied in three male subjects. The“arm+leg”exercise was performed in ten different ways with different arm load ranging from 14 to 60% of the total work load. VO2 and VE were found higher in the arm exercise than in the other types of exercise at submaximal work. At a given work load, the lowest HR was observed in the“arm+leg”exrcise when the arm was loaded with 14 to 33% of the total work load. And the highest HR was obtained in the arm exercise. The higher HR during the arm exercise as compared to the legor“arm + leg”exercise may be accounted for by the fact that an exercise with small muscle group appears to elicit lower stroke volume and more pronounced rise in sympathetic tone. In the“arm + leg”exercise, HR at a given work load or VO2 varied with the proportion of arm load. However VE, whcih might be affected by stroke volume, was unaffected by the rate of arm to the total work load at a given work load or VO2. This indicates that the sympathetic tone may be affected by the proportion of work load distribution on the active msucle groups in the“arm + leg”exercise.
