Optimal exercise dose and modality-specific effects on lower-limb balance and functional motor performance in middle-aged and older adults with stroke: a Bayesian network meta-analysis.

Abstract

Objective: To compare the effects of different exercise modalities on lower-limb balance and functional motor performance after stroke and to examine their nonlinear dose-response relationships to identify potentially optimal exercise doses using a Bayesian network meta-analysis.

Methods: A systematic search of PubMed, Embase, Web of Science, the Cochrane Library, and SPORTDiscus identified 54 randomized controlled trials (RCTs). A Bayesian random-effects dose-response network meta-analysis examined associations between total exercise dose, exercise modalities, and lower-limb balance and functional mobility after stroke.

Results: Both lower-limb balance and functional movement outcomes showed clear nonlinear improvements with increasing total exercise doses, peaking at approximately 1,800-2,200 MET×min/week. Beyond this range, marginal benefits plateaued or declined, with greater inter-individual variability. For lower-limb balance, gains stabilized or slightly decreased past 2,200 MET×min/week. Functional movement improvements formed an early plateau at around 1,800 MET×min/week, sustained up to 2,200, then gradually diminished. Exercise modalities displayed distinct dose sensitivities: integrated aerobic training (IAT) rapidly achieved peak benefits at moderate loads, supporting early rehabilitation; motor control training (MCT) maintained stable effects over a broader range, facilitating long-term neuromuscular reinforcement; virtual reality training (VRT) showed localized peaks at low to moderate doses but exhibited increased uncertainty at higher levels.

Conclusions: This study suggests that moderate weekly exercise doses may improve lower-limb balance and functional mobility after stroke, with dose-response patterns differing across exercise modalities. These findings support dose regulation and individualized exercise prescription, although further high-quality trials are needed to confirm the observed dose ranges and modality-specific effects.