Comparative Effectiveness of Unstable Versus Stable Resistance Training on Lower Limb Strength, Mobility, and Fear of Falling in Older Adults

OBJECTIVE: This meta-analysis compares the effectiveness of unstable resistance training (URT) with stable resistance training (SRT) on lower limb strength, mobility, and fear of falling in older adults. DESIGN: PubMed, Embase, Web of Science, Scopus, and the Cochrane Library were searched through July 9, 2025, for randomized controlled trials (RCTs) comparing URT with SRT in older adults. Outcomes included lower limb strength (maximal isometric leg extension strength, Five-Times Sit-to-Stand test), mobility (Timed Up and Go test, gait speed), and fear of falling (Falls Efficacy Scale-International test). Data were pooled separately for short-term (10 to 12 wk) and long-term (24 wk) interventions. RESULTS: Seven RCTs reported in 8 articles were included; 6 contributed to outcome-specific meta-analyses, and 1 was analyzed descriptively. After short-term training, URT showed no significant improvements over SRT in lower limb strength and mobility outcomes; for the Five-Times Sit-to-Stand test, SRT demonstrated a nonsignificant trend toward better performance than URT. URT significantly reduced fear of falling after short-term training and significantly improved Timed Up and Go performance following long-term training compared with SRT. CONCLUSIONS: URT may provide more benefits over SRT in reducing fear of falling in older adults, with greater functional gains after long-term training.