Cardiovascular Responses to Electrical Stimulation-Induced Leg Cycling Versus Voluntary Arm Cranking Exercise

The roles of absolute and relative oxygen uptake (VO2 and percent of muscle group specific VO2 max) as determinants of the cardiovascular and ventilatory responses to exercise over a wide range of active muscle mass have not previously been defined. Six healthy men performed four types of dynamic exercise--one-arm curl, one-arm cranking, and one- and two-leg cycling at four different relative work loads--25, 50, 75, and 100% of VO2 max for the corresponding muscle group. VO2 during maximal one-arm curl, one-arm cranking, and one-leg cycling averaged 20, 50, and 75%, respectively, of that for maximal two-leg cycling. Cardiac output was linearly related to VO2 with a similar slope and intercept for each type of exercise. Heart rate at a given %VO2 max was higher with larger active muscle mass. In relation to %VO2 max, systemic resistance was lower and plasma catecholamine levels were higher with larger active muscle mass. The cardiovascular responses to exercise are determined to a large extent by the active muscle mass and the absolute oxygen uptake, with the principal feature appearing to be the tight linkage between systemic oxygen transport and utilization.

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Moderate-intensity Arm-cranking Exercise may not Improve Arterial Function in Healthy Adult Men

International Journal of Sports Medicine ◽

10.1055/a-0664-8823 ◽

2018 ◽

Vol 39 (13) ◽

pp. 962-966

Author(s):

Hajime Miura ◽

Miduki Ishikawa ◽

Kenichi Deguchi

Keyword(s):

Healthy Adult ◽

Acute Effect ◽

Moderate Intensity ◽

Upper Arm ◽

Arm Cranking ◽

Cycling Exercise ◽

Arterial Function ◽

Adult Men ◽

Leg Cycling ◽

Arm Cranking Exercise

AbstractEndurance exercises, such as cycling or running, are useful for improving arterial function. However, people suffering from partial paralysis or arthritis are unable to perform these kinds of lower-limb exercises. In the present study, we explored the acute effect of upper-arm exercise on arterial stiffness in healthy men. Fourteen healthy adult men performed two experimental trials. The order of experiments was randomized between a 30-min arm-cranking exercise at 50% V̇O2max (A-trial) and a 30-min leg-cycling exercise at 50% V̇O2max (C-trial). The brachial to ankle pulse wave velocity (baPWV), brachial systolic/diastolic blood pressure and heart rate were obtained with subjects in the supine position. The baseline hemodynamic values were not markedly different between the two trials. Compared with the baseline value, the baPWV was significantly reduced at 30 and 60 min after the C-trial. In the A-trial, however, there were no significant changes in the baPWV throughout the trial. These results indicate that acute 50% V̇O2max arm-cranking exercise induced relatively little change in the baPWV, which was the opposite of the finding observed with leg-cycling exercise. Therefore, in order to improve arterial function via aerobic upper-arm exercises, the exercise mode/intensity or other approaches should be considered.

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