The position of the cuff bladder has a large impact on the pressure needed for blood flow restriction

OBJECTIVE: A recent study suggested that measuring the blood flow restriction pressure every training session may not be needed given the relative stability of this measurement over an eight week period of time. However, within clinical and research settings, various personnel may apply the cuff differently resulting in the cuff bladder being in dissimilar positions. Understanding the effect (if any) of bladder position may help with the standardization of blood flow restriction and ensure the proper stimulus is applied. Therefore, the purpose of this study was to measure and compare arterial occlusion pressures in the lower body between medial and lateral bladder positions. APPROACH: Thirty-two participants volunteered to have their arterial occlusion pressure measured thrice in their right leg. The 12 cm cuff was applied twice with the bladder covering the inner portion of their thigh (to establish agreement with itself) and once with the bladder covering the lateral portion. Effects are reported as median (95% credible interval). MAIN RESULTS: There was evidence the outside bladder position required greater pressure to occlude blood flow than the inside position (median difference of 13.56 (7.29, 19.84) mmHg). The agreement between inside and outside bladder positions had a mean difference of 14.3 (lower limit of agreement -19.7, upper limit of agreement 48.3) mmHg. The agreement was worse with individuals with larger thigh circumferences (r = 0.558 (0.24, 0.74)). SIGNIFICANCE: Cuff bladder position should be standardized to account for pressure differences. Standardizing bladder position may reduce the need to measure arterial occlusion pressure every time blood flow restriction is used.