Too Little Research to Know How Cannabis Affects Athletic Performance
A systematic review found only three trials examining marijuana's effects on athletic performance, with insufficient evidence to draw conclusions about most outcomes including heart rate, blood pressure, and exercise duration.
Quick Facts
What This Study Found
Only three trials met inclusion criteria. Low-quality evidence suggested marijuana may increase bronchodilation but decrease physical work capacity. No significant effects on grip strength were found. The evidence for effects on heart rate, blood pressure, and exercise duration remained unclear due to study limitations.
Key Numbers
Only 3 trials found. Two had high risk of bias, one had unclear risk. Low-quality evidence for both ergogenic (bronchodilation) and ergolytic (decreased work capacity) effects.
How They Did This
Systematic review searching MEDLINE, EMBASE, CINAHL, PsycINFO, AMED, and SPORTDiscus through September 2016. Study quality assessed using Cochrane tools.
Why This Research Matters
Despite widespread cannabis use among athletes, the scientific evidence base for its effects on performance is remarkably thin. This review highlights a major knowledge gap in an area of significant practical importance.
The Bigger Picture
Cannabis is banned in competition by the World Anti-Doping Agency, yet there is essentially no evidence it enhances performance. This disconnect between policy and evidence raises questions about the basis for cannabis prohibition in sports.
What This Study Doesn't Tell Us
Only three studies met inclusion criteria, all with significant limitations. No meta-analysis possible due to heterogeneity. Studies were older and used smoked marijuana, which may differ from modern products.
Questions This Raises
- ?Does cannabis actually impair athletic performance enough to justify competition bans?
- ?Could CBD (without THC) benefit recovery without affecting performance?
- ?Do chronic versus acute effects differ in athletes?
Trust & Context
- Key Stat:
- Only 3 trials exist on cannabis and athletic performance - a remarkable evidence gap given the prevalence of use and its prohibited status in sports.
- Evidence Grade:
- Preliminary - systematic methodology is rigorous, but only three low-quality studies were available.
- Study Age:
- Published in 2018. Cannabis in sports research remains limited.
- Original Title:
- Marijuana and Its Effects on Athletic Performance: A Systematic Review.
- Published In:
- Clinical journal of sport medicine : official journal of the Canadian Academy of Sport Medicine, 28(4), 350-357 (2018)
- Authors:
- Trinh, Kien V, Diep, Dion, Robson, Hannah
- Database ID:
- RTHC-01860
Evidence Hierarchy
Analyzes all available research on a topic using a structured method.
What do these levels mean? →Frequently Asked Questions
Does cannabis improve athletic performance?
There is essentially no evidence that cannabis enhances athletic performance. This systematic review found only three trials, with low-quality evidence suggesting marijuana may slightly improve lung function but decrease physical work capacity.
Why is cannabis banned in sports if there is no evidence it helps performance?
This review highlights the disconnect: cannabis is banned in competition by anti-doping authorities, but there is virtually no evidence it enhances performance. Only three trials have ever studied the question directly.
Read More on RethinkTHC
Cite This Study
https://rethinkthc.com/research/RTHC-01860APA
Trinh, Kien V; Diep, Dion; Robson, Hannah. (2018). Marijuana and Its Effects on Athletic Performance: A Systematic Review.. Clinical journal of sport medicine : official journal of the Canadian Academy of Sport Medicine, 28(4), 350-357. https://doi.org/10.1097/JSM.0000000000000471
MLA
Trinh, Kien V, et al. "Marijuana and Its Effects on Athletic Performance: A Systematic Review.." Clinical journal of sport medicine : official journal of the Canadian Academy of Sport Medicine, 2018. https://doi.org/10.1097/JSM.0000000000000471
RethinkTHC
RethinkTHC Research Database. "Marijuana and Its Effects on Athletic Performance: A Systema..." RTHC-01860. Retrieved from https://rethinkthc.com/research/trinh-2018-marijuana-and-its-effects
Access the Original Study
Study data sourced from PubMed, a service of the U.S. National Library of Medicine, National Institutes of Health.
This study breakdown was produced by the RethinkTHC research team. We analyze and report published research findings without making health recommendations. All interpretations are based solely on the published abstract and study data.