Trends and Practices on Blood Flow Restriction Training Are Not Largely Aligned With the Contemporary Evidence

Abstract

Objective: To evaluate trends and current clinical practice of physiotherapists on blood flow restriction training (BFRT) application.

Methods: An online survey was conducted to assess: a) demographics and professional characteristics, b) specifics of BFRT application, and c) safety and adverse events. We tested using Pearson's Chi-square test whether the physiotherapist's characteristics were independent of their years of experience and formal BFR education.

Results: Most respondents reported having much confidence (n=47, 44.6%) in using BFRT, and they used it for a mean of 2.6±1.7 years. Significant variability among respondents was found in devices used, limb occlusion pressure calculation methods, the reperfusion scheme, the number of exercises implemented, and the percentage of complete occlusion pressure used for exercising. Most used BFRT in musculoskeletal conditions of the upper and lower limb (n=88, 86.3%), aiming improvements in strength and muscle volume (n=93, 90.3%), by using external load (n=82, 79.6%). The majority of the respondents (n=69, 67.0% attended a short course for BFRT, of which 55.1% (n=56) believed it was not evidence-based. No significant associations were found between the years of experience or attendance in a BFRT course with practices and perceptions of the surveyed physiotherapists (all p>0.05). Conclusion: Current BFRT practices are largely not aligned with contemporary scientific evidence and recommendations.

Keywords: bfr training; blood flow restriction; clinical practice; rehabilitation; safety.

Figure 1. Physiotherapists responses in survey items enquiring about the application of BFRT in clinical practice

Responses to questions: a) “How did you learn about Blood Flow Restriction training?”, b) “Why do you use Blood Flow Restriction?”, c) “What percentage or millimeters of mercury (mmHg) do you usually use for upper extremity blood flow restriction?”, and d) “What percentage or centimeters of mercury (mmHg) do you usually use for lower extremity restriction?” Note: Bars indicate percentages (%) of the total sample size (n=103). BFRT, blood flow restriction training; MSc, master’s degree; ROM, range of motion; MSK, musculoskeletal.

Figure 2. Physiotherapists’ responses in survey items enquiring about exercise loading during the application of BFRT in clinical practice.

Physiotherapists’ responses in survey items enquiring about exercise loading during the application of BFRT in clinical practice. Responses to questions: a) “In combination with what type of exercise/activity do you use blood flow restriction?” and b) “How do you determine the external load or resistance in a blood flow restriction session?”. Note: In part (a), bars indicate percentages (%) of the total sample size (n=103), but in part (b), bars represent counts (multiple selection items). BFRT, blood flow restriction training; NPRS, numeric pain rating scale; 1RM, one repetition maximum; BW, body weight.

Figure 3. Physiotherapists’ responses in survey items enquiring about barriers and concerns in the application of BFRT, the absolute risk factors, and the use in musculoskeletal conditions.

Responses to questions: a) “What barriers, concerns, or difficulties do you have regarding the use of blood flow restriction in your clinical practice?”, b) “In which of the following conditions would you perform an intervention with blood flow restriction?”, and c) “Which of the following do you consider as absolute risk factors for an intervention with blood flow restriction?”. Note: In parts (b) and (c), bars indicate percentages (%) of the total sample size (n=103), but in (a), bars represent the percentage of the respondents who identified barriers and have concerns about BFRT application (n=60). BFRT, blood flow restriction training; MSK, musculoskeletal; ACLR, anterior cruciate ligament reconstruction; OCD, osteochondral defect; LET, lateral elbow tendinopathy; RC, rotator cuff; PFPS, patellofemoral pain syndrome; NPRS, numeric pain rating scale; DVT, deep venous thrombosis; PE, pulmonary embolism.