The Influence of Cuff Width and Sex on Arterial Occlusion

Abstract

PURPOSE: To examine differences in arterial occlusion pressure (AOP) of the upper arm when applying cuff widths (5 cm, 10 cm, and 12 cm) commonly used in blood flow restriction (BFR) research. This study also examined how individual predictors of AOP changed across cuff widths. METHODS: Two hundred forty-nine (102 males and 147 females) participants visited the laboratory once. Height, body mass, arm length, and arm circumference were assessed. Following a 10-minute rest, brachial blood pressure was measured (systolic = bSBP and diastolic = bDBP). With a rest period of 5-minutes before each measurement, standing AOP was determined on the right arm for each cuff (counterbalanced) using a Doppler probe placed at the radial artery. Hierarchical linear regression was used to determine which predictors explained the most unique variance in AOP for each cuff width. To examine sex differences in AOP across cuff widths, a repeated measures ANOVA was used with a between subject factor of sex. If an interaction was found, a Fishers LSD test identified differences between cuff widths within each sex, and independent t-tests were used to examine differences for sex within each cuff width. Effect sizes were determined by calculating Cohen’s d. Data is presented as mean (standard deviation). RESULTS: Occlusion pressure was different across cuff widths (p < 0.001). The 5 cm wide cuff required the greatest pressure [145 (19) mmHg], followed by the 10 cm [123 (13) mmHg], and 12 cm [120 (12) mmHg] wide cuffs. A model of arm circumference, bSBP, arm length, bDBP, and sex explained the most variance in AOP for all three cuff widths (5 cm, R2 = 0.651; 10 cm, R2 = 0.570; 12 cm, R2 = 0.557). However, arm circumference always explained the most unique variance in AOP (5 cm, Part = .554; 10 cm, Part = .419; 12 cm, Part = .406). Differences in AOP existed between sexes for the 5 cm [males 149 (19) vs females 142 (19) mmHg, p = 0.003, d = 0.36], 10 cm [males 127 (13) vs females 121 (13) mmHg, p = 0.002, d = 0.46], and 12 cm [males 122 (12) vs females 118 (12) mmHg, p = 0.009, d = 0.33] wide cuffs. CONCLUSIONS: The cuff width used for BFR has a significant impact on AOP in the upper arm. Future studies should acknowledge this, and ensure cuff width is reported. Further, individual differences, primarily arm circumference, should be accounted for when applying relative inflation pressures.