Partial occlusion during resistance exercise alters effort sense and pain

The purpose of the study was to determine how manipulation of peripheral blood flow during resistance exercise using a light load affected perception and physiological measures compared with moderate load resistance exercise and a control trial. Seven subjects performed a 3 (session) by 2 (biceps curls and calf extensions) within-subjects study that was randomized and counterbalanced across 3 weeks. The 3 sessions included (a) light resistance exercise (3 sets to failure) at 30% of 1 repetition maximum (1RM) with partial occlusion (LRO), (b) moderate resistance at 70% of 1RM with no occlusion (MR), and (c) partial occlusion without exercise (OO). Ratings of perceived exertion (RPE), pain, and heart rate were assessed immediately after each set, whereas blood samples were taken before, immediately after, and 15 minutes after exercise. Results demonstrated that RPE and pain were lower in the OO condition than that in the MR and LRO conditions for biceps curls and calf extensions, Fs(2 ,24) = 22.75, 20.86, ps < 0.0001 and Fs(2,24) = 18.95, 24.52, ps < 0.01; however, no significant differences were noted between MR and LRO conditions. Heart rate was significantly higher for the LRO condition when compared with the MR trial, F(2,18) 20.12, p < 0.001. Results suggest that when partial vascular occlusion with a light load was applied, both pain and effort sense were altered to a similar degree as moderate loads but no occlusion. The practical application of results were that individuals may be better able to tolerate perceptual change at low loads with partial occlusion because joint stress may be minimized while local muscle metabolic demands increase, making resistance training maximally effective and minimally stressful on joints. Perceptual tracking of effort and pain may aid coaches who attempt this protocol.