Acute Cardiovascular Responses To Resistance Training With And Without Blood Flow Restriction

Abstract

Recently, it has been suggested that resistance exercise (RE) can be applied for cardiovascular function, maintenance and/or for rehabilitation purposes. PURPOSE: To compare the acute effects of high intensity RE (HI), low intensity RE (LI) and low intensity RE with blood flow restriction (LI-BFR) on heart rate (HR) and blood pressure (BP) in healthy subjects. METHODS: 52 subjects ((27.3±7 years; BMI: 27.3±3.1) were assigned into three groups: High intensity (HI, 75%-1RM; n=15); low intensity (LI, 30%- 1RM; n=13); and low intensity with blood flow restriction training (LI-BFR, 30%-1RM and 30% of total vascular restriction; n=24). All participants performed 4 sets of plantar flexion in the leg press machine with 1 set of 30 repetitions following 3 sets of 15 (for LI and LI-BFR group) or 10 repetitions (HI group). Blood flow restriction was achieved using a cuff positioned on the dominant calf. The cuff was inflated at 30% of total vascular restriction of each individual (mean: 47.6 ± 19.8 mmHg). Cardiovascular variables were obtained during and after the session. RESULTS: Results indicated that HR increased significantly during the 4 exercise set for all groups (p <0.05), although the highest increases were found during the last set for the HI group (pre: 70.0±10.0 bpm; post: 81.6±11.7 bpm; p<0.001) and during the first set for the LI-BFR group (pre: 66.1±12.9 bpm; post: 73.7±15.1bpm; p<0.001). There were no significant differences in BP for any group. However, significant intergroup differences were observed in systolic BP during the first set for HI and LI-BFR groups when compared to LI group (p=0.03). HI and LI-BFR promoted significant systolic BP reductions (p<0.001) 30min post-exercise (pre: 126.1±11.7 mmHg; post: 112.3±14.0 mmHg), 45min post-exercise (pre: 126.1±11.7 mmHg; post: 113.1±10.2 mmHg) and for HI group post-15min (pre: 123.6±15.7 mmHg; post: 115.0±15.9 mmHg), post-45min (pre: 123.6±15.7 mmHg; post: 114.4±16.7 mmHg) and post-60min (pre: 123.6±15.7 mmHg; post: 113.3±14.7 mmHg). There were no significant changes (p>0.05) for diastolic BP and HR of the LI-BFR group. CONCLUSION: LI-BFR resistance training is able to generate an acute hemodynamic and cardiovascular response similar to HI and LI resistance exercise. HI and LI-BFR seem to promote a hypotensive post-exercise response.