CBD Made Runners Feel Calmer but Didn't Change Their Running Performance

Randomized, crossover design with 12 runners (4 male, 8 female, mean age 25.5). Each participant completed two sessions: one with 300 mg oral CBD capsules and one with placebo, separated by a washout period. Two hours post-ingestion: State Trait Anxiety Inventory, resting blood pressure, heart rate, blood lactate, and HRV measured. Then a 2-mile treadmill time trial at maximum effort. Heart rate, RPE, and blood lactate measured during and after the run. GI symptom questionnaire post-run.

CBD is widely marketed to athletes and increasingly used in sports. The World Anti-Doping Agency removed CBD from its prohibited list in 2018. This pilot study provides some of the first controlled data on acute CBD effects during actual running performance — finding mood benefits without performance changes.

This adds an exercise-performance dimension to CBD research. The anxiolytic effect is consistent with broader CBD anxiety findings, while the lack of performance impact suggests CBD isn't ergogenic. The exercise-endocannabinoid connection explored in RTHC-00145 (exercise and the ECS in cancer patients) provides the physiological context — exercise itself modulates the endocannabinoid system, and adding exogenous CBD on top doesn't appear to further enhance physical output.

Very small sample (12 participants). Acute single-dose study — chronic CBD use might produce different effects. 300 mg is a relatively high dose; lower doses common in commercial products might not even produce the mood effects seen here. Only tested 2-mile running; other exercise types (strength, HIIT, ultra-endurance) might respond differently. Two-hour absorption window may not be optimal for all individuals. No blood CBD levels measured to confirm absorption.