Effects Of Upper And Lower Body Blood Flow Restriction Training On Subjective Assessments

PURPOSE: To characterize the effects of upper and lower body autoregulated blood flow restriction (AR-BFR), non-autoregulated BFR (NAR-BFR), and no BFR on rating perceived exertion (RPE), rating perceived discomfort (RPD), and gauge of a 1-10 Likert scale on the likelihood of performing the exercise training again. AR-BFR pressure cuffs adjust pressure automatically, maintaining a similar pressure during concentric and eccentric phases. However, NAR-BFR pressure cuffs do not accommodate for larger muscle diameters during the concentric phase, creating higher limb pressures compared to the eccentric phase. METHODS: Accordingly, 33 adults (21 ± 2 years; 11 females) participated in the upper body and 20 adults (23 ± 5 years; 7 females) participated in the lower body in treatment-order exercise sessions with AR-BFR, NAR-BFR, and no BFR in a randomized fashion separated by 1-week and included a familiarization session. All participants in the upper body sessions performed four sets of dumbbell curls and all participants in the lower body sessions performed four sets of wall squats with handheld dumbbells to volitional fatigue using 20% of their 1-RM with 2-second cadence and 1 minute rest periods. Cuffs were placed at the proximal portion of the arms and thighs, and limb occlusion pressure (LOP) was set at 60% of supine LOP for both BFR treatments during the exercise and rest periods for both the upper and lower body sessions, respectively. Subjective measurements of RPE, RPD, and the 1-10 Likert scale were taken immediately post-exercise while the cuffs were inflated. Two-way ANOVAs were conducted on variables of interest. RESULTS: There were no significant differences in RPE between AR-BFR, NAR-BFR, and no BFR in the upper and lower body sessions (p = 0.13). There was a significant difference in RDP between upper body AR-BFR and no BFR (mean difference (MD) = 2.23 ± 0.47, p < 0.01) and upper body NAR-BFR and no BFR (mean difference (MD) = 1.32 ± 0.47, p = 0.05). CONCLUSION: The use of BFR does not appear to influence subjective ratings of exertion in the upper and lower limbs. Additionally, AR-BFR and NAR-BFR devices may cause more subjective discomfort compared to no BFR.