Effects of resistance training on muscle strength in adults with haemophilia: A systematic review and meta-analysis

Abstract Introduction Although resistance training is frequently prescribed for people with haemophilia (PWH), no previous meta-analyses have quantified the effect of this intervention on muscle strength, nor the implications of the intervention's modality and duration. Aim (1) To determine the effects of resistance training on muscle strength in adults with haemophilia; (2) To determine the most effective duration and modality among the exercise protocols. Methods A systematic search from inception until 28 November 2023 was conducted in PubMed, Embase, Web of Science, CENTRAL and CINAHL databases. We included randomised controlled trials or before-after studies that involved resistance training without other physiotherapy co-interventions. Study selection, data extraction and risk of bias assessment were independently performed by two reviewers. Disagreements were resolved in consultation with a third author. The level of evidence was determined according to the GRADE methodology. Results Seven studies were included. Measurements of knee extensor strength and elbow extensor strength were included in the meta-analysis. Subgroup analysis showed significant effects for both elastic resistance protocols (SMD: 0.54; 95% CI: 0.02?1.07) and conventional training (isometric and weight-based equipment) (SMD: 0.88; 95% CI: 0.50?1.25), demonstrating small and moderate effect sizes respectively. Additionally, both protocols of duration 5?7 weeks (SMD: 1.16, 95% CI: 0.63?1.69) as well as those of duration ≥8 weeks (SMD: 0.57, 95% CI: 0.20?0.94) showed a significant difference. Conclusion Resistance training is effective in improving muscle strength of the knee and elbow extensors in PWH. Both elastic resistance and conventional training show benefits.