Exercise and Motor Complications in Parkinson's Disease: A Systematic Review and Meta-Analysis

Levodopa remains the most effective pharmacological treatment for Parkinson's disease (PD), but long-term use commonly leads to motor complications such as levodopa-induced dyskinesia (LID) and motor fluctuations, significantly contributing to disability. Exercise is well-established for improving motor and non-motor symptoms in PD; however, its effect on motor complications remains unclear.

To determine whether exercise reduces motor complications in people with PD.

Systematic searches were conducted in five databases. Eligible randomized controlled trials assessed motor complications pre- and post- exercise intervention using the Unified Parkinson's Disease Rating Scale IV (UPDRS IV) or its modified version were included. Methodological quality was assessed using the Physiotherapy Evidence Database scale. Studies rated as good quality and reporting sufficient outcome data were included in a random-effects meta-analysis. Meta-regression analyses explored potential moderating effects of medication status (on/off) and control group type (active/passive).

Twenty-three studies were included; 14 were rated as good quality, of which 11 provided sufficient data for meta-analysis. Sample sizes ranged from 11 to 125 participants, and interventions varied in type, intensity and duration. Meta-analysis showed no significant effect of exercise on motor complications. Meta-regression analyses showed no moderating effect of medication status or control group type.

Current evidence does not support an effect of exercise on LID or motor fluctuations in PD. These findings should be interpreted with caution, given the low baseline severity of motor complications (UPDRS IV 3.47), small sample sizes, heterogeneity of interventions, and the absence of trials specifically designed to target motor complications.