Cannabis Before Exercise: Elevated Spirits, Same Speed
BOULDER, Colo. — A new study suggests that consuming cannabis before a workout may enhance how exercise feels—making it more enjoyable and uplifting mood—but the same doesn’t hold for improving physical performance. The research, published in Sports Medicine, reveals a nuanced picture: cannabis may change the psychology of movement, but it doesn’t appear to be a shortcut to better athletic results.
Mood over muscle
Researchers from the University of Colorado Boulder recruited 42 regular runners who were already accustomed to combining cannabis and exercise. Participants were randomly assigned to use either a THC-dominant or CBD-dominant cannabis product prior to one exercise session and performed a “sober” run in another session for comparison.
During the runs, participants were periodically asked to rate how motivated they felt, how much they enjoyed it, whether time seemed to pass faster, and how hard the effort felt. On average, runners reported higher enjoyment, more positive affect, and a more intense “runner’s high” when exercising after cannabis use—whether THC or CBD.
Interestingly, the CBD group often reported greater gains in mood and enjoyment compared to the THC group, and with fewer side effects in terms of perceived effort.
The performance paradox
Despite the mood boost, cannabis use did not translate into better performance. In some instances, runners in the THC group reported the same intensity of exercise felt significantly more difficult.
This difficulty may stem in part from cannabis’ physiological effects: THC is known to increase heart rate, which could make a run feel more strenuous. Moreover, in prior related work, cannabis users ran about 31 seconds slower per mile when high—a small but measurable decrement in performance.
The authors of the study emphasize that cannabis should not be viewed as an “ergogenic” aid—i.e., a substance that enhances performance. “It is pretty clear from our research that cannabis is not a performance-enhancing drug,” said senior author Angela Bryan.
Broader context & caveats
The findings come at a time of growing interest in how cannabis and its components (notably THC and CBD) interact with the body’s endocannabinoid system, which is implicated in mood, pain perception, and inflammation. Some researchers speculate that cannabis may allow exercisers to “tap into” sensations similar to the endogenous cannabinoids naturally produced during extended physical activity.
However, the study has limitations. It focused on recreational runners who were already comfortable combining cannabis and exercise, which may limit generalizability. In addition, the time delay between cannabis use and exercise onset (on average about 32 minutes) introduces variability in drug effects. Researchers also caution that cannabis can carry risks — such as dizziness, impaired coordination, and increased heart rate — especially in high-intensity or coordination-demanding workouts.
Outside the lab, many athletes already believe cannabis helps with recovery. Surveys in trained users show that 90-plus percent believe CBD helps with post-exercise recovery, and a substantial portion attribute similar effects to THC. That said, these are self-reports and not controlled experiments, so the evidence remains incomplete.
What it means — and what’s next
The study paints a compelling picture: cannabis use prior to exercise may not make you faster or stronger, but it might make you want to exercise more often by making it feel better. As the authors note, overcoming the inertia or discomfort barrier is a big challenge in public health, and tools that make movement more pleasurable are worth exploring — albeit with caution about possible downsides.
Future research will need to examine different doses, strains, modes of delivery (e.g. edibles vs. inhalation), longer-term effects, and whether certain populations (such as less active individuals) could benefit more from the mood-enhancing effects. For now, cannabis before exercise appears to hold more promise for “feel-good” than for “performance boost.”