Effects of individualized blood flow restriction during brief twice-weekly low-load cycling on mobility and muscle function in adults older than 70 years.

Abstract

Introduction: Age-related declines in muscle strength and physical function increase the risk of mobility limitations, disability, and loss of independence. Although resistance training is effective, many older adults are unable or unwilling to perform high-load exercise, highlighting the need for time-efficient, low-load interventions that preserve physical function. Blood flow restriction (BFR) training may enhance adaptations to low-load exercise, but whether a brief, clinically feasible endurance-based BFR intervention can induce clinically meaningful improvements in mobility remains unclear.

Methods: Twenty adults aged >70 years were randomized to six weeks of supervised low-load cycling (15 min, twice weekly) with either BFR at 60% limb occlusion pressure (INT, n = 11) or sham BFR (20mmHg, CON, n = 9). Primary outcomes were functional mobility, assessed by the DEMMI, and health-related quality of life. Secondary outcomes included Timed Up and Go (TUG), Six-Minute-Walking-Test (6MWT), lower-limb strength, handgrip strength, body composition, endurance capacity, and cardiovascular safety.

Results: INT showed significantly greater improvements in functional mobility (DEMMI) compared to CON [baseline-adjusted ANCOVA: p = 0.02; Hedges' g [standardized between-group contrast, 95% CI] = 0.91 [-0.04 to 1.87]]. In secondary analyses, no significant between-group differences were observed for TUG [p = 0.14; g = -0.68 (-1.61 to 0.25)] or 6MWT distance [p = 0.08; g = 0.79 (-0.15 to 1.73)]. However, INT showed significant improvements in lower-limb strength with no relevant improvements in CON [leg press: p = 0.04, g = 0.98 [0.02 to 1.94]; leg extension: p < 0.01, g = 1.52 [0.49 to 2.56]]. Furthermore, significant improvements were also observed in muscle mass and endurance capacity (p < 0.05), as well as in health-related quality of life, including vitality [baseline-adjusted ANCOVA: p = 0.042, adjusted mean difference = 6.94 (0.29 to 13.6)] and mental health [p < 0.001, g = 1.61 (0.53 to 2.68)]. Handgrip strength was preserved in INT despite a significant decline in CON (p = 0.042). In secondary exploratory analyses, HDL cholesterol increased, and HbA1c decreased (p < 0.05). Echocardiography revealed no adverse structural or functional cardiac adaptations, and no adverse events occurred.

Conclusion: A brief, twice-weekly low-load cycling program combined with BFR elicited significant rises in lower-limb strength with associated clinically meaningful improvements in mobility despite a minimal exercise dose. Endurance-based BFR appears to be a feasible, safe, and well-tolerated strategy to improve physical function and support independent living in healthy older adults. This trial was not prospectively registered in a public trial registry. It was retrospectively registered at ClinicalTrials.gov (registration number: NCT07825987).