Segura · Frontiers in neurology 2020 · parallel-group controlled clinical trial · n=13

Effect of a High-Intensity Tandem Bicycle Exercise Program on Clinical Severity, Functional Magnetic Resonance Imaging, and Plasma Biomarkers in Parkinson's Disease.

Cited 30 times in the scientific literature.

Level 2 - randomized trial

Individual parallel-group controlled clinical trial

PubMed 32793096 · doi:10.3389/fneur.2020.00656 · record verified 2026-08-30

What was done

In a single-center, parallel-group clinical trial, 13 patients with Parkinson's disease aged 65 or younger were assigned to either a control group or an exercise intervention group. Both groups continued standard Parkinson's disease medications. The intervention group completed a 16-week tandem cycling program at 80% of maximum heart rate (target cadence ≥80 rpm), 3 times weekly. Outcomes measured at baseline and week 16 included Unified Parkinson's Disease Rating Scale (UPDRS) scores, VO2 max, functional MRI (fMRI), anthropometry, and plasma biomarkers.

What was found

VO2 max improved by 5.7 ml/kg/min in the cycling group and decreased by 1.6 ml/kg/min in controls (p = 0.041). UPDRS scores decreased by 5.7 points in the intervention group versus an increase of 0.9 points in controls, but the difference was not statistically significant (p = 0.11). Plasma BDNF increased >10-fold in the intervention group and declined in controls (p = 0.028); larger BDNF increases correlated with greater UPDRS improvements (r = -0.58, p = 0.04). Task fMRI revealed right fusiform gyrus activation and altered functional connectivity between the cingulum and frontal cortex, and cerebellar vermis with thalamus and posterior temporal gyrus.

Why it matters

High-intensity tandem cycling can improve cardiorespiratory fitness and substantially increase circulating BDNF in Parkinson's disease patients. However, clinical motor improvements did not achieve statistical significance compared to control.

Limits

The sample size was very small (n = 13 total across two arms), resulting in low statistical power. The primary clinical metric (UPDRS change) failed to show statistically significant between-group differences. The cohort was limited to patients aged 65 or younger at a single site.

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