Hemodynamic response to resistance exercise with and without blood flow restriction in healthy subjects

PurposeTo compare the hemodynamic response during resistance exercise at high intensity (HI), low intensity (LI) and low intensity with blood flow restriction (LI-BFR) in healthy subjects. MethodsTwelve men performed three sets of unilateral knee extension exercises at LI-BFR and LI (15 repetitions; 20% of 1RM) and HI (8 repetitions; 80% of 1RM). The blood flow restriction was accomplished using a sphygmomanometer positioned on the thigh and inflated to the point of blood flow interruption (1679166mmHg). The hemodynamic variables were obtained by continuous beat-to-beat photoplethysmography. Rating of perceived exertion (RPE) and blood lactate were also measured. ResultsThe HI session showed higher values (P<005) in all sets than the LI and LI-BFR for diastolic blood pressure, heart rate and rate-pressure product. The LI-BFR showed higher values than the LI only in the 3rd set for systolic blood pressure, heart rate and rate-pressure product. Blood lactate was higher in the HI (42 +/- 02mmol) and LI-BFR (41 +/- 03mmol) than the LI (35 +/- 03mmol). Rating of perceived exertion was higher in the LI-BFR (79 +/- 03) than the HI (64 +/- 04) and LI (32 +/- 04). ConclusionThe LI-BFR session exhibited similar blood lactate to the HI, a higher rating of perceived response than the HI and LI, and equal or lower hemodynamic responses than the HI.