H J Thomas1, B R Scott2, J J Peiffer2. 1. School of Psychology and Exercise Science, Murdoch University, Australia. Electronic address: Hannah.thomas@research.uwa.edu.au. 2. School of Psychology and Exercise Science, Murdoch University, Australia.
Abstract
OBJECTIVES:Blood flow restriction (BFR) during interval cycling may stimulate aerobic and anaerobic adaptations. However, acute physiological responses to BFR interval cycling have not been extensively investigated. DESIGN:Eighteen males completedlow-intensity (LI), low-intensity with BFR (LIBFR) and high-intensity (HI) interval cycling sessions in randomised and counterbalanced order. These included a standardised warm-up and three two-min intervals interspersed with two-min recovery. Interval intensity during HI, LI and LIBFR were 85%, 40% and 40% of peak power output obtained during graded exercise tests. METHODS: During LIBFR, 80% arterial occlusion was applied to both legs during the interval efforts and removed during recovery. Continuous measures of heart rate (HR), cardiac output (CO) and oxygen consumption (V˙O2) were recorded. Blood pressure (BP) and rating of perceived exertion (RPE) were measured following intervals. Blood lactate concentration was measured pre- and post-exercise. RESULTS:BP, HR, CO, V˙O2, lactate and RPE were greatest during HI. During the active intervals, BP, HR and CO were greater during LIBFR than LI. V˙O2 during recovery periods were greater in LIBFR than LI. Post-session lactate was greater during LIBFR than LI. Importantly, mean arterial pressure during interval three was significantly greater in LIBFR (124±2mmHg) than HI (114±3mmHg). CONCLUSIONS:LIBFR increases cardiovascular and metabolic stress compared with LI and could provide an alternative aerobic training method for individuals unable to perform high-intensity exercise. However, increases in mean arterial pressure during LIBFR indicates high myocardial workload, and practitioners should therefore use caution if prescribing LIBFR for vascular compromised individuals.
RCT Entities:
OBJECTIVES: Blood flow restriction (BFR) during interval cycling may stimulate aerobic and anaerobic adaptations. However, acute physiological responses to BFR interval cycling have not been extensively investigated. DESIGN: Eighteen males completed low-intensity (LI), low-intensity with BFR (LIBFR) and high-intensity (HI) interval cycling sessions in randomised and counterbalanced order. These included a standardised warm-up and three two-min intervals interspersed with two-min recovery. Interval intensity during HI, LI and LIBFR were 85%, 40% and 40% of peak power output obtained during graded exercise tests. METHODS: During LIBFR, 80% arterial occlusion was applied to both legs during the interval efforts and removed during recovery. Continuous measures of heart rate (HR), cardiac output (CO) and oxygen consumption (V˙O2) were recorded. Blood pressure (BP) and rating of perceived exertion (RPE) were measured following intervals. Blood lactate concentration was measured pre- and post-exercise. RESULTS: BP, HR, CO, V˙O2, lactate and RPE were greatest during HI. During the active intervals, BP, HR and CO were greater during LIBFR than LI. V˙O2 during recovery periods were greater in LIBFR than LI. Post-session lactate was greater during LIBFR than LI. Importantly, mean arterial pressure during interval three was significantly greater in LIBFR (124±2mmHg) than HI (114±3mmHg). CONCLUSIONS: LIBFR increases cardiovascular and metabolic stress compared with LI and could provide an alternative aerobic training method for individuals unable to perform high-intensity exercise. However, increases in mean arterial pressure during LIBFR indicates high myocardial workload, and practitioners should therefore use caution if prescribing LIBFR for vascular compromised individuals.
Authors: Júlio Cesar Gomes Silva; Elísio Alves Pereira Neto; Patrick Alan Souza Pfeiffer; Gabriel Rodrigues Neto; Amanda Santos Rodrigues; Michael G Bemben; Stephen D Patterson; Gilmário Ricarte Batista; Maria S Cirilo-Sousa Journal: Front Physiol Date: 2019-10-04 Impact factor: 4.566