Across 15 published studies, THC showed no improvement in aerobic performance, probably reduced strength, and triggered angina at lower workloads in 100% of cardiac-vulnerable subjects.
Read this if you exercise or play sports and use cannabis and want to know how it affects your performance and safety.
Zero out of 15 studies showed aerobic performance improvement from THC
What the researchers found
This systematic review searched for all published studies investigating THC's effects during formal exercise protocols, finding only 15 studies in the entire literature.
None of the 15 studies showed any improvement in aerobic exercise performance from THC. One positive finding was that cannabis inhibited exercise-induced asthma, suggesting possible bronchodilatory effects during physical activity.
The detrimental effects were more notable. Two studies found that marijuana triggered angina (chest pain) at lower workloads than normal in 100% of subjects tested, a significant cardiovascular safety concern. Strength was probably reduced. Some participants could not complete exercise protocols due to adverse reactions caused by cannabis.
A finding relevant to drug testing: aerobic exercise caused only very small rises in blood THC concentrations (less than 1 ng/mL), suggesting that exercise-induced fat mobilization does not meaningfully release stored THC.
Why it matters
Despite cannabis being one of the most commonly detected substances in athlete drug testing, this review reveals remarkably little evidence that it enhances performance. The cardiovascular risks (angina at lower workloads) are particularly concerning for recreational exercisers who use cannabis.
The numbers in context
Only 15 published studies exist on THC and exercise. Zero showed aerobic improvement. 100% of cardiac-vulnerable subjects experienced angina at lower workloads. Exercise caused THC blood rises of less than 1 ng/mL.
How the study worked
Systematic review searching PubMed, Medline, and Embase for cannabis/THC in sport and exercise. Included studies with formal exercise protocols or rehabilitation/health screening programs. Excluded review articles, opinion pieces, and policy statements.
What this study cannot tell us
Only 15 studies were found, reflecting the extremely limited research base. Many studies were older and used varying cannabis preparations, doses, and exercise protocols. The small number of studies prevents strong conclusions about specific exercise types or populations.
How to read the evidence
Systematic review with clear methodology. Moderate because the underlying evidence base is limited to only 15 studies with varied protocols.
When this study was published
Published in 2017, searching literature through early 2017.
The bigger picture
The lack of performance enhancement raises questions about why cannabis remains on some sport banned substance lists. If the primary concern is athlete health rather than performance advantage, the evidence for cardiovascular risk during exercise may be the more relevant policy consideration.
Questions still open
- Could cannabis offer recovery benefits (pain, sleep, inflammation) that indirectly support athletic performance even if it does not directly enhance it? Should cannabis be treated differently from performance-enhancing drugs in sport? Does CBD have different exercise effects than THC?
Common questions
Does cannabis improve athletic performance?
Is it dangerous to exercise after using cannabis?
Read the original research
Cannabis: Exercise performance and sport. A systematic review.
Journal of science and medicine in sport, 20(9), 825-829
Citation
Kennedy, Michael C. (2017). Cannabis: Exercise performance and sport. A systematic review.. Journal of science and medicine in sport, 20(9), 825-829. https://doi.org/10.1016/j.jsams.2017.03.012
Explore the wider topic
- Athletes and Cannabis: Performance, Recovery, and Quitting
- Healthcare Workers and Cannabis: Nurses, Doctors, and Hidden Use
- Quitting Weed for Your Career: How Cannabis Affects Work and What Changes When You Stop
- Cannabis and College: Academic Impact and Quitting Weed as a Student
- Cannabis and Your Body: What the Research Actually Shows
- THC and Running: The Runner's High Connection
- THC and Golf: The Silicon Valley Open Secret