Impact of leg blood flow restriction during walking on central arterial hemodynamics

Abstract

Walking exercise with limb blood flow restriction (BFR) has been shown to increase muscular mass and strength even if it is performed at low exercise intensities. Despite mounting evidence for its efficacy and the increasing popularity, the safety of BFR exercise in relation to cardiac loads has not been established. The aim of this study was to determine the response of central hemodynamics during the BFR exercise to assess its impact on cardiac load. Fifteen apparently healthy sedentary or recreationally active adults (10 men and 5 women, 27 ± 1 yr) underwent five bouts of 2-min constant treadmill walking at 2 mph with 1-min rest intervals either with or without BFR on both proximal thighs. Beat-by-beat blood pressure and hemodynamics (via Modelflow method) were measured, and central arterial hemodynamics were evaluated with pulse wave analyses via general transfer function. Incident wave amplitude (IWA) and reflected wave amplitude (RWA) were obtained by the wave separation analysis. Peripheral systolic blood pressure (SBP) increased more substantially during walking with BFR (43 ± 5% vs. baseline) than without BFR (11 ± 4% vs. baseline). Aortic SBP did not change significantly during walking without BFR, but there was a substantial elevation in aortic SBP (43 ± 5% vs. baseline) during walking with BFR. Significant effect of BFR was seen in IWA but not in RWA. These findings suggest that even during slow-speed walking, leg BFR induces substantial hypertensive responses in the aorta. However, this response could not be explained by the augmented wave reflection.

Hemodynamic responses are reduced with aerobic compared with resistance blood flow restriction exercise

“…The similar hemodynamic responses between LI and LI+BFR are in contrast to previous reports that observed increased blood pressures with aerobic BFR exercise to levels greater than an equal-intensity control exercise bout, combined with a greater HR and reduced SV while maintaining _ Q (Renzi et al 2010;Staunton et al 2015;Sugawara et al 2015;Ozaki et al 2010). Typically, such different responses to BFR exercise between studies may be attributed to factors associated with the application of BFR such as cuff width and cuff pressure (Loenneke et al 2012a), and the exercise type (Staunton et al 2015), combined with individual factors such as limb circumference (Loenneke et al 2012a).…”

“…LI and LI+BFR required participants to walk at a velocity of 4 km·h −1 as used previously (Sugawara et al. ; Renzi et al. ).…”

“…For the TM trial, all sets were 2-min in duration. LI and LI+BFR required participants to walk at a velocity of 4 kmÁh À1 as used previously (Sugawara et al 2015;Renzi et al 2010). HI required participants to run at a velocity equivalent to 80% V O 2 max as a workload representative of a high submaximal intensity.…”

Hemodynamic and Pressor Responses to Combination of Yoga and Blood Flow Restriction

“…An application of BFR during walking exercises has been associated with greater RPE [2,7,30]. In the present study using yoga, there was no significant difference between the conditions in reported RPE throughout the exercise duration.…”

Ischaemic and hypoxic conditioning: potential for protection of vital organs

“…While aerobic BFRE is less studied than resistance BFRE, several investigations have compared the haemodynamic responses to an acute bout of aerobic BFRE. Greater elevations in arterial pressures in response to treadmill walking with blood flow restriction applied to the upper thighs compared to non‐restricted exercise at the same intensity have been reported (Renzi, Tanaka, & Sugawara, ; Sugawara, Tomoto, & Tanaka, ). However, the intensities of BFRE and control exercise were not matched based on heart rate or in these studies.…”