Local muscle endurance with open and occluded intramuscular circulation

¹ Faculty of Education, The University of Western Australia, Nedlands, Western Australia

The local isometric endurance of the elbow flexors of four groups of five female subjects was tested. Two groups had the circulation to the contracting muscles occluded by a pressure cuff and the others had normal circulations. One group in each of the open and occluded conditions worked with a load equivalent to one-third of maximum strength and the other group worked against a resistance of two-thirds of maximum strength. The endurances of the two groups working with two-thirds of maximum strength as load were not significantly different despite the occlusion of the blood supply in one of the groups. The endurance of the group with open circulation and one-third of maximum strength as load was significantly greater than that of the group with the same load but with occluded blood supply. Only at this lower level of loading did the artificial occlusion of the blood supply to the active muscle group appear to reduce its endurance.