Immediate effects of high-speed cycling intervals on bradykinesia in Parkinson's disease.

There is growing evidence that speed-based exercise training benefits people with Parkinson's disease (PD). The present study investigates the effects of a single session of volitional, high-speed cycling intervals on a battery of timed functional tests selected for their relevance to the symptom of bradykinesia. Ten subjects with PD (Hoehn-Yahr stage ≤ 3.0) participated in a familiarization session and three test sessions. Functional testing occurred before and after 30 minute sessions in which subjects performed no exercise (NO), pedaled at their preferred cadence (PC), or performed 20, 15-second intervals of high-speed low-resistance cycling (HS-LR). In addition to testing the exercise effects in a within-subjects design, we provide test-retest reliability data, minimal detectable change scores, and correlations among the selected functional tests. Despite the relatively low dose of speed-based exercise, HS-LR elicited significant (p < 0.05) improvements in the four square step test and 10 m walk test. Excepting reaction times, there was high reliability and adequate sensitivity to detect moderate and small differences. Strong correlations among tests of mobility inform the future selection of measures in the experimental design. In addition to what is known about continuous exercise sessions involving high-speed exercise, the present results suggest that brief intervals of HS-LR bicycling are promising and should be examined in a longer duration exercise program.