Feasibility and safety of two weeks of blood flow restriction exercise in individuals with spinal cord injury

CONTEXT: Reduced muscle strength and function are common after spinal cord injury (SCI). While low-load blood flow restriction exercise (BFRE) enhances muscle strength in healthy and clinical populations, its safety and feasibility in individuals with SCI remain underexplored. OBJECTIVES: To investigate the feasibility and safety of low-load BFRE in individuals with incomplete SCI. STUDY DESIGN: Case series. SETTING: SCI rehabilitation center. PARTICIPANTS: Six participants with motor incomplete SCI were enrolled in the study. INTERVENTION: A two-week BFRE intervention for the lower limbs was conducted twice weekly at 40% total arterial occlusion pressure, using 30-40% of 1-repetition maximum loads. OUTCOME MEASURES: Feasibility measures, specifically recruitment and eligibility rates and intervention acceptability, were collected. Blood pressure (BP) responses and specific coagulation markers for deep vein thrombosis (DVT) were assessed as safety measures. RESULTS: Recruitment and eligibility rates were 2.8% and 6.6% for individuals admitted for first-time rehabilitation (subacute SCI) and 8.3% and 13.9% for 4-week readmission rehabilitation stays (chronic SCI), respectively. Intervention acceptability was high, characterized by 95.8% training adherence and low-to-moderate self-reported pain levels. BP responses and changes in C-reactive protein, Fibrinogen, and D-dimer during the intervention remained within clinically acceptable levels. CONCLUSION: BFRE was feasible in an SCI rehabilitation setting despite a low recruitment rate. BFRE imposed no heightened risk of DVT or severe BP fluctuations in the present case series. Additionally, no severe adverse events occurred, and only mild complaints were reported. More extensive safety considerations warrant larger-scale exploration. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT03690700.