Limb occlusion pressure for blood flow restricted exercise: Variability and relations with participant characteristics

Objective: Assess lower-extremity blood flow restricted exercise (BFR) limb occlusion pressure (LOP) variability and identify related intrinsic characteristics using a portable Delphi BFR system. Design: Repeated measures. Setting: Laboratory. Participants: Forty-two healthy males (n = 25) and females (n = 17) (25.8 ± 5.2 y, 1.76 ±0 .09 m, 78.9 ± 14.9 kg) completed two visits. Brachial artery blood pressure, thigh circumferences (TC), and LOP were measured supine. Main outcome measures: Linear mixed-effects models (LMM) and generalizability theory were used to evaluate LOP between legs and days, determine intrinsic characteristic relations, and assess random variance components. Results: LOP was not different between legs (p = .730) or days (p = .916; grand mean = 183.7 mmHg [178.4, 189.1]). LOP varied significantly between participants (p = .011, standard error = 47.3 mmHg). 47% of LOP variance was between participants, 18% and 6% was within participants between days and legs, respectively, and 28% was associated with random error. The relative error variance was 14.4 mmHg. Pulse pressure (PP) (p = .005) and TC (p = .040) were positively associated with LOP. A LMM including PP and TC predicted LOP with a mean absolute difference of 11.1 mmHg [9.7, 12.6] compared to measured LOP. Conclusions: The relative error variance suggests that clinicians should measure LOP consistently for each patient to ensure BFR safety and effectiveness.