The effect of a clinically practical exercise on levodopa bioavailability and motor response in patients with Parkinson disease.

Objective: The aim of the study was to investigate the potential effect of short, moderate intensity (e70% maximum heart rate) cyclette exercise on levodopa (LD)/dopa decarboxylase inhibitor bioavailability and motor response in a subgroup of Parkinson disease (PD) patients presenting a moderate-to-severe delay in fasting morning LD dose absorption and matched motor response. Methods: Ten patients underwent an oral LD instrumental kinetic-dynamic test based on simultaneous serial measurements of plasma LD concentrations, finger tapping motor effects, dyskinesia ratings plus Unified Parkinson Disease Rating Scale Motor Section (section III) evaluation after ingestion of their usual fasting first morning LD dose, on 2 occasions, 2 weeks apart, according to an intrasubject randomized cross-over design: once receiving their oral LD test dose immediately before a 15-minute cycling and once at seated rest. The main LD pharmacokinetic variables were time to peak, peak plasma concentration, and the area under the 4-hour plasma concentration-time curve. The main LD pharmacodynamic variables were the latency, duration of the motor effect elicited by the LD test dose, and the area under the 4-hour tapping effect-time curve. Results: The LD pharmacokinetics and pharmacodynamics did not differ between the 2 sessions. Conclusions: We found no significant effect of a moderate, clinically practical exercise on LD rate and extent of absorption and matched motor response in a subgroup of patients with delayed LD kinetic-dynamic effect.