In 2021, the International Olympic Committee (IOC) banned American sprinter, Sha’Carri Richardson, from the Tokyo Olympics after she tested positive for marijuana.
This naturally led to a media brouhaha with some folks rebuking the IOC for banning an athlete for a recreational drug, and others blasting Richardson for being so careless as to put a banned substance in her body right before the Olympics.
This also quickened a longstanding debate in sports: is marijuana performance enhancing?
Many gym-goers are curious to know the answer to a related question: will marijuana interfere with my gains?
In this article, we’re going to dive into the scientific research to give you evidence-based answers to both questions. You’ll learn what marijuana is, whether it enhances athletic performance or impedes muscle growth, and more.
What Is Marijuana?
“Marijuana” refers to the dried leaves, flowers, stems, and seeds of the Cannabis sativa or Cannabis indica plant—a plant that contains the mind-altering chemical tetrahydrocannabinol (THC).
The Chinese have used marijuana as an analgesic (pain-relieving) and psychoactive drug since around 2700 BC. Today, marijuana is the most widely used illicit drug globally. An estimated 188 million adults worldwide used marijuana in 2017, which is just under 4% of the global adult population.
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Is Marijuana A Performance-Enhancing Drug?
There are several ways that marijuana may affect performance. Let’s consider each separately.
Marijuana and Aerobic Performance
In a review conducted by scientists at St. Vincent’s Hospital Medical School, researchers analyzed the results of 15 studies and found that marijuana had no positive effects on aerobic performance. Specifically, the researchers found that smoking marijuana hastens fatigue, increases perceived exertion, decreases work capacity (the amount of exercise you’re able to complete), and makes you feel dizzy, which can prevent you from completing your workout.
Another review conducted by scientists at the University of Toronto examined four studies that looked at marijuana’s effect on aerobic performance and found that two studies showed marijuana had no effect, and two studies showed marijuana negatively impacted performance.
Finally, a recent umbrella review (a review of several reviews) concluded that:
“Cannabis consumption has an ergolytic effect on exercise performance and therefore does not act as a sport performance enhancing agent as raised by popular beliefs. Thus, cannabis consumption prior to exercise should be avoided in order to maximize performance in sports.”
Furthermore, research shows that long-term marijuana smoking can severely impair respiratory health. While this isn’t direct proof that marijuana use stymies aerobic performance, it makes it difficult to see how marijuana could have a favorable effect.
In other words, it’s not a stretch of the imagination to think that smoking grass hurts your lung health, and thus your endurance.
Marijuana and Strength
Only two studies have investigated the effect of marijuana use on strength. One found that strength was unaffected by marijuana use, while the other reported that “weakness was clearly demonstrated” after using marijuana, though it didn’t give more detail.
Both studies only measured grip strength and neither used athletes as participants, though, so it’s not clear if these results apply to weightlifters.
While it’s purely speculative, some researchers believe that marijuana may increase strength through bronchodilation (relaxing the muscles in the lungs and widening the airways).
Research shows that beta-2 agonists (drugs that cause bronchodilation) such as salbutamol, salmeterol, formoterol, and terbutaline can improve strength, sprint, and power performance in nonasthmatic people.
Since short-term marijuana use is associated with bronchodilation, it could theoretically have a similar effect to other beta-2 agonists (though this has never been proven in research).
Finally, for strength to be effectively employed in a sporting context, you must be focused and precise. That is, you can be extremely strong but fail to express that strength effectively if you have trouble concentrating and using good technique.
Research shows that using marijuana can hinder hand-eye coordination, focus, and decision-making, which may increase the chances that you don’t use your strength when you need it.
Marijuana and Muscle Growth
No studies have looked at the effects of marijuana on muscle growth, so it’s impossible to draw any firm conclusions about how grass affects your gains.
Even speculation is difficult because there’s so much conflicting research.
On the one hand, studies on how marijuana affects anabolic (muscle-building) hormones shows that THC drastically lowers testosterone in rats and rhesus monkeys. On the other hand, human trials are a mixed bag, with some showing THC lowers testosterone and growth hormone and others finding that it has no effect.
If we take these findings together with what we know about how marijuana might impact strength and your ability to train effectively, there’s enough reason to believe that marijuana could hinder your ability to build muscle (even indirectly), which means that you should probably steer clear of it if building muscle is your top priority.
Marijuana and Pain
Athletes have used cannabis to relieve pain for millennia (it was one of the ingredients in the “Fuscum Olympionico inscriptum,” or the Olympic Victors Dark Ointment used at the classic Olympics).
A large meta-analysis conducted by scientists at the University of Bristol that included 79 studies and a total of 6,462 participants found evidence that marijuana can treat pain and spasticity (muscle spasms).
Thus, marijuana may indirectly boost athletic performance by helping athletes deal with the aches and pains that accompany regular competition.
What’s more, research shows that smoking marijuana increases pain tolerance, which may also give athletes a competitive edge by allowing them to train and compete through pain that might sideline other athletes.
Marijuana and Recovery
Sleep is essential for most athletes because it gives the body a chance to recover from the rigors of training and the brain a break from the pressure of regular competition.
Studies show that marijuana can increase sleep duration, which may improve performance by aiding recovery.
Marijuana and Anxiety
Marijuana lowers anxiety, which helps some athletes to reach a “flow state” and be more creative. It may also scrub “fear memories,” so athletes are less afraid of what might go wrong and more likely to perform without the fear of failure.
Conclusion
Based on the weight of the scientific evidence, it’s reasonable to conclude that marijuana doesn’t improve athletic performance and may even prevent you from performing at your best (especially in endurance sports).
The only way that marijuana may indirectly boost performance is through its ability to promote recovery, which it primarily does by making it easier to sleep. It may also improve your ability to cope with pain, which could aid performance in some scenarios. However, if you’re injury-free, it’s unlikely to have any positive impact on your athletic abilities.
Some people believe that marijuana increases creativity and makes it easier to enter a “flow state,” though this is purely anecdotal and may not be the same for everyone (some studies show that smoking marijuana makes it more difficult to concentrate and hinders decision-making).
FAQ #1: Is Marijuana Safe?
Many people think of marijuana as a mild drug with medicinal benefits with fewer adverse health effects than similar legal substances such as alcohol.
And while research shows that marijuana is effective at treating some medical conditions, including pain, anxiety, and depression, and safer than alcohol in some ways, it’s probably an overstatement to refer to marijuana as “safe.”
For example, research shows that regular long-term marijuana use is associated with . . .
- Changes in amygdala, hippocampal, and white and gray matter volume, and blood flow in the brain
- Changes in learning, attention, memory, and overall brain activity
- Disruptions in important brain chemicals such as glutamate, dopamine, N-acetylaspartate, myo-inositol, choline, and γ-aminobutyric acid
- Mental health related issues, like earlier onset of psychosis, depression, and anxiety
- Increased risk of stroke, atrial fibrillation, respiratory complications, chronic obstructive pulmonary disease, and testicular cancer
- Increased risk of tobacco and nicotine dependence
FAQ #2: Does marijuana enhance athletic performance?
No.
Most research shows that using marijuana either has no effect on your athletic performance or prevents you from performing at your best.
That said, using marijuana may improve your recovery and help you deal with pain better, which means it may indirectly enhance athletic performance in some situations.
FAQ #3: Does weed affect muscle growth?
There’s no research looking at how “weed” (marijuana) affects muscle growth directly.
However, marijuana may make you weaker (at least for a short time) and can make you less proficient at tasks that require coordination, both of which would hinder your ability to train effectively and could decrease the amount of muscle you build over time.
FAQ #4: Can smoking weed make you lose muscle?
No.
It may hinder how quickly you build muscle, though, by making . . .
- Your workouts feel more difficult
- You feel tired
- You weaker
- You less able to perform exercises effectively
Thus, it’s sensible to avoid marijuana if you want to gain muscle and strength as quickly as possible.
+ Scientific References
- Zuardi, A. W. (2006). History of cannabis as a medicine: a review. Revista Brasileira de Psiquiatria (Sao Paulo, Brazil : 1999), 28(2), 153–157. https://doi.org/10.1590/S1516-44462006000200015
- Vereinte Nationen Office on Drugs and Crime. (n.d.). World drug report 2019.
- Kennedy, M. 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
- Rotstein, A., & Sagiv, M. (1986). Acute effect of cigarette smoking on physiologic response to graded exercise. International Journal of Sports Medicine, 7(6), 322–324. https://doi.org/10.1055/s-2008-1025784
- Avakian, E. V., Horvath, S. M., Michael, E. D., & Jacobs, S. (1979). Effect of marihuana on cardiorespiratory responses to submaximal exercise. Clinical Pharmacology and Therapeutics, 26(6), 777–781. https://doi.org/10.1002/CPT1979266777
- Tashkin, D. P., Shapiro, B. J., Lee, Y. E., & Harper, C. E. (1976). Subacute Effects of Heavy Marihuana Smoking on Pulmonary Function in Healthy Men. New England Journal of Medicine, 294(3), 125–129. https://doi.org/10.1056/nejm197601152940302
- Benowitz, N. L., & Jones, R. T. (1977). Prolonged delta-9-tetrahydrocannabinol ingestion. Effects of sympathomimetic amines and autonomic blockades. Clinical Pharmacology and Therapeutics, 21(3), 336–342. https://doi.org/10.1002/CPT1977213336
- Docter, S., Khan, M., Gohal, C., Ravi, B., Bhandari, M., Gandhi, R., & Leroux, T. (2020). Cannabis Use and Sport: A Systematic Review. Sports Health, 12(2), 189–199. https://doi.org/10.1177/1941738120901670
- Charron, J., Carey, V., Marcotte L’Heureux, V., Roy, P., Comtois, A. S., & Ferland, P. M. (2021). Acute effects of cannabis consumption on exercise performance: a systematic and umbrella review. The Journal of Sports Medicine and Physical Fitness, 61(4), 551–561. https://doi.org/10.23736/S0022-4707.20.11003-X
- Tetrault, J. M., Crothers, K., Moore, B. A., Mehra, R., Concato, J., & Fiellin, D. A. (2007). Effects of Marijuana Smoking on Pulmonary Function and Respiratory Complications: A Systematic Review. Archives of Internal Medicine, 167(3), 221. https://doi.org/10.1001/ARCHINTE.167.3.221
- Hollister, L. E., Richards, R. K., & Gillespie, H. K. (1968). Comparison of tetrahydrocannabinol and synhexyl in man. Clinical Pharmacology and Therapeutics, 9(6), 783–791. https://doi.org/10.1002/CPT196896783
- Huestis, M. A., Mazzoni, I., & Rabin, O. (2011). Cannabis in Sport: Anti-Doping Perspective. Sports Medicine (Auckland, N.Z.), 41(11), 949. https://doi.org/10.2165/11591430-000000000-00000
- Riiser, A., Stensrud, T., Stang, J., & Andersen, L. B. (2020). Can β2-agonists have an ergogenic effect on strength, sprint or power performance? Systematic review and meta-analysis of RCTs. British Journal of Sports Medicine, 54(22), 1351–1359. https://doi.org/10.1136/BJSPORTS-2019-100708
- Tashkin, D. P., Reiss, S., Shapiro, B. J., Calvarese, B., Olsen, J. L., & Lodge, J. W. (1977). Bronchial effects of aerosolized delta 9-tetrahydrocannabinol in healthy and asthmatic subjects. The American Review of Respiratory Disease, 115(1), 57–65. https://doi.org/10.1164/ARRD.1977.115.1.57
- Tashkin, D. P., Shapiro, B. J., & Frank, I. M. (1974). Acute effects of smoked marijuana and oral delta9-tetrahydrocannabinol on specific airway conductance in asthmatic subjects. The American Review of Respiratory Disease, 109(4), 420–428. https://doi.org/10.1164/ARRD.1974.109.4.420
- Laviolette, M., & Belanger, J. (1986). Role of prostaglandins in marihuana-induced bronchodilation. Respiration; International Review of Thoracic Diseases, 49(1), 10–15. https://doi.org/10.1159/000194853
- Tashkin, D. P., Shapiro, B. J., & Frank, I. M. (1973). Acute pulmonary physiologic effects of smoked marijuana and oral (Delta)9 -tetrahydrocannabinol in healthy young men. The New England Journal of Medicine, 289(7), 336–341. https://doi.org/10.1056/NEJM197308162890702
- Volkow, N. D., Baler, R. D., Compton, W. M., & Weiss, S. R. B. (2014). Adverse Health Effects of Marijuana Use. The New England Journal of Medicine, 370(23), 2219. https://doi.org/10.1056/NEJMRA1402309
- Morrison, P. D., Zois, V., McKeown, D. A., Lee, T. D., Holt, D. W., Powell, J. F., Kapur, S., & Murray, R. M. (2009). The acute effects of synthetic intravenous Delta9-tetrahydrocannabinol on psychosis, mood and cognitive functioning. Psychological Medicine, 39(10), 1607–1616. https://doi.org/10.1017/S0033291709005522
- Ramaekers, J. G., Kauert, G., Van Ruitenbeek, P., Theunissen, E. L., Schneider, E., & Moeller, M. R. (2006). High-potency marijuana impairs executive function and inhibitory motor control. Neuropsychopharmacology : Official Publication of the American College of Neuropsychopharmacology, 31(10), 2296–2303. https://doi.org/10.1038/SJ.NPP.1301068
- Boyden, T. W., & Pamenter, R. W. (1983). Effects of ethanol on the male hypothalamic-Pituitary-Gonadal axis. Endocrine Reviews, 4(4), 389–395. https://doi.org/10.1210/edrv-4-4-389
- Besch, N. F., Smith, C. G., Besch, P. K., & Kaufman, R. H. (1977). The effect of marihuana (delta-9-tetrahydrocannabinol) on the secretion of luteinizing hormone in the ovariectomized rhesus monkey. American Journal of Obstetrics and Gynecology, 128(6), 635–642. https://doi.org/10.1016/0002-9378(77)90209-5
- Kolodny, R. C., Masters, W. H., Kolodner, R. M., & Toro, G. (1974). Depression of plasma testosterone levels after chronic intensive marihuana use. The New England Journal of Medicine, 290(16), 872–874. https://doi.org/10.1056/NEJM197404182901602
- Brown, T. T., & Dobs, A. S. (2002). Endocrine effects of marijuana. Journal of Clinical Pharmacology, 42(S1). https://doi.org/10.1002/J.1552-4604.2002.TB06008.X
- Benowitz, N. L., Jones, R. T., & Lerner, C. B. (1976). Depression of growth hormone and cortisol response to insulin-induced hypoglycemia after prolonged oral delta-9-tetrahydrocannabinol administration in man. The Journal of Clinical Endocrinology and Metabolism, 42(5), 938–941. https://doi.org/10.1210/JCEM-42-5-938
- Mendelson, J. H., Kuehnle, J., Ellingboe, J., & Babor, T. F. (1974). Plasma testosterone levels before, during and after chronic marihuana smoking. The New England Journal of Medicine, 291(20), 1051–1055. https://doi.org/10.1056/NEJM197411142912003
- CF, S., CG, G., & KM, D. (1975). Letter: Normal plasma testosterone concentrations after marihuana smoking. The New England Journal of Medicine, 292(16), 867–868. https://doi.org/10.1056/NEJM197504172921615
- Block, R. I., Farinpour, R., & Schlechte, J. A. (1991). Effects of chronic marijuana use on testosterone, luteinizing hormone, follicle stimulating hormone, prolactin and cortisol in men and women. Drug and Alcohol Dependence, 28(2), 121–128. https://doi.org/10.1016/0376-8716(91)90068-A
- Bartels, E. M., Swaddling, J., & Harrison, A. P. (2006). An ancient Greek pain remedy for athletes. Pain Practice : The Official Journal of World Institute of Pain, 6(3), 212–218. https://doi.org/10.1111/J.1533-2500.2006.00088.X
- Whiting, P. F., Wolff, R. F., Deshpande, S., Di Nisio, M., Duffy, S., Hernandez, A. V., Keurentjes, J. C., Lang, S., Misso, K., Ryder, S., Schmidlkofer, S., Westwood, M., & Kleijnen, J. (2015). Cannabinoids for Medical Use: A Systematic Review and Meta-analysis. JAMA, 313(24), 2456–2473. https://doi.org/10.1001/JAMA.2015.6358
- Tesarz, J., Schuster, A. K., Hartmann, M., Gerhardt, A., & Eich, W. (2012). Pain perception in athletes compared to normally active controls: a systematic review with meta-analysis. Pain, 153(6), 1253–1262. https://doi.org/10.1016/J.PAIN.2012.03.005
- Bergamaschi, M. M., & Crippa, J. A. S. (2013). Why should Cannabis be Considered Doping in Sports? Frontiers in Psychiatry, 4. https://doi.org/10.3389/FPSYT.2013.00032
- Eichner, E. R. (1993). Ergolytic drugs in medicine and sports. The American Journal of Medicine, 94(2), 205–211. https://doi.org/10.1016/0002-9343(93)90185-R
- Huestis, M. A., Mazzoni, I., & Rabin, O. (2011). Cannabis in sport: anti-doping perspective. Sports Medicine (Auckland, N.Z.), 41(11), 949–966. https://doi.org/10.2165/11591430-000000000-00000
- Izquierdo, I., Furini, C. R. G., & Myskiw, J. C. (2016). Fear Memory. Physiological Reviews, 96(2), 695–750. https://doi.org/10.1152/PHYSREV.00018.2015
- Corroon, J., & Phillips, J. A. (2018). A Cross-Sectional Study of Cannabidiol Users. Cannabis and Cannabinoid Research, 3(1), 152. https://doi.org/10.1089/CAN.2018.0006
- Connor, J. P., Haber, P. S., & Hall, W. D. (2016). Alcohol use disorders. The Lancet, 387(10022), 988–998. https://doi.org/10.1016/S0140-6736(15)00122-1
- Babor, T. F. (2010). Alcohol and Public Policy Group. https://doi.org/10.1111/j.1360-0443.2010.02945.x
- Rehm, J., Marmet, S., Anderson, P., Gual, A., Kraus, L., Nutt, D. J., Room, R., Samokhvalov, A. V., Scafato, E., Trapencieris, M., Wiers, R. W., & Gmel, G. (2013). Defining substance use disorders: Dowe really need more than heavy use? Alcohol and Alcoholism, 48(6), 633–640. https://doi.org/10.1093/ALCALC/AGT127
- Forouzanfar, M. H., Alexander, L., Bachman, V. F., Biryukov, S., Brauer, M., Casey, D., Coates, M. M., Delwiche, K., Estep, K., Frostad, J. J., Astha, K. C., Kyu, H. H., Moradi-Lakeh, M., Ng, M., Slepak, E., Thomas, B. A., Wagner, J., Achoki, T., Atkinson, C., … Zhu, S. (2015). Global, regional, and national comparative risk assessment of 79 behavioural, environmental and occupational, and metabolic risks or clusters of risks in 188 countries, 1990-2013: A systematic analysis for the Global Burden of Disease Study 2013. The Lancet, 386(10010), 2287–2323. https://doi.org/10.1016/S0140-6736(15)00128-2/ATTACHMENT/8ECECF19-44E8-4A5A-843A-B063BA3F32E2/MMC1.PDF
- Lorenzetti, V., Lubman, D. I., Whittle, S., Solowij, N., & Yücel, M. (2010). Structural MRI findings in long-term cannabis users: what do we know? Substance Use & Misuse, 45(11), 1787–1808. https://doi.org/10.3109/10826084.2010.482443
- Batalla, A., Bhattacharyya, S., Yücel, M., Fusar-Poli, P., Crippa, J. A., Nogué, S., Torrens, M., Pujol, J., Farré, M., & Martin-Santos, R. (2013). Structural and Functional Imaging Studies in Chronic Cannabis Users: A Systematic Review of Adolescent and Adult Findings. PLOS ONE, 8(2), e55821. https://doi.org/10.1371/JOURNAL.PONE.0055821
- Wrege, J., Schmidt, A., Walter, A., Smieskova, R., Bendfeldt, K., Radue, E.-W., Lang, U., & Borgwardt, S. (2014). Effects of cannabis on impulsivity: a systematic review of neuroimaging findings. Current Pharmaceutical Design, 20(13), 2126–2137. https://doi.org/10.2174/13816128113199990428
- Martín-Santos, R., Fagundo, A. B., Crippa, J. A., Atakan, Z., Bhattacharyya, S., Allen, P., Fusar-Poli, P., Borgwardt, S., Seal, M., Busatto, G. F., & McGuire, P. (2010). Neuroimaging in cannabis use: a systematic review of the literature. Psychological Medicine, 40(3), 383–398. https://doi.org/10.1017/S0033291709990729
- Batalla, A., Crippa, J. A., Busatto, G. F., Guimaraes, F. S., Zuardi, A. W., Valverde, O., Atakan, Z., McGuire, P. K., Bhattacharyya, S., & Martín-Santos, R. (2014). Neuroimaging studies of acute effects of THC and CBD in humans and animals: a systematic review. Current Pharmaceutical Design, 20(13), 2168–2185. https://doi.org/10.2174/13816128113199990432
- Quickfall, J., & Crockford, D. (2006). Brain neuroimaging in cannabis use: a review. The Journal of Neuropsychiatry and Clinical Neurosciences, 18(3), 318–332. https://doi.org/10.1176/JNP.2006.18.3.318
- Sneider, J. T., Mashhoon, Y., & Silveri, M. M. (2013). A Review of Magnetic Resonance Spectroscopy Studies in Marijuana using Adolescents and Adults. Journal of Addiction Research & Therapy, Suppl 4. https://doi.org/10.4172/2155-6105.S4-010
- Colizzi, M., McGuire, P., Pertwee, R. G., & Bhattacharyya, S. (2016). Effect of cannabis on glutamate signalling in the brain: A systematic review of human and animal evidence. Neuroscience and Biobehavioral Reviews, 64, 359–381. https://doi.org/10.1016/J.NEUBIOREV.2016.03.010
- Sami, M. B., Rabiner, E. A., & Bhattacharyya, S. (2015). Does cannabis affect dopaminergic signaling in the human brain? A systematic review of evidence to date. European Neuropsychopharmacology : The Journal of the European College of Neuropsychopharmacology, 25(8), 1201–1224. https://doi.org/10.1016/J.EURONEURO.2015.03.011
- Lev-Ran, S., Roerecke, M., Le Foll, B., George, T. P., McKenzie, K., & Rehm, J. (2014). The association between cannabis use and depression: a systematic review and meta-analysis of longitudinal studies. Psychological Medicine, 44(4), 797–810. https://doi.org/10.1017/S0033291713001438
- Crippa, J. A., Zuardi, A. W., Martín-Santos, R., Bhattacharyya, S., Atakan, Z., McGuire, P., & Fusar-Poli, P. (2009). Cannabis and anxiety: a critical review of the evidence. Human Psychopharmacology, 24(7), 515–523. https://doi.org/10.1002/HUP.1048
- Hackam, D. G. (2015). Cannabis and stroke: systematic appraisal of case reports. Stroke, 46(3), 852–856. https://doi.org/10.1161/STROKEAHA.115.008680
- Korantzopoulos, P., Liu, T., Papaioannides, D., Li, G., & Goudevenos, J. A. (2008). Atrial fibrillation and marijuana smoking. International Journal of Clinical Practice, 62(2), 308–313. https://doi.org/10.1111/J.1742-1241.2007.01505.X
- Martinasek, M. P., McGrogan, J. B., & Maysonet, A. (2016). A Systematic Review of the Respiratory Effects of Inhalational Marijuana. Respiratory Care, 61(11), 1543–1551. https://doi.org/10.4187/RESPCARE.04846
- Gurney, J., Shaw, C., Stanley, J., Signal, V., & Sarfati, D. (2015). Cannabis exposure and risk of testicular cancer: a systematic review and meta-analysis. BMC Cancer, 15(1). https://doi.org/10.1186/S12885-015-1905-6
- Rubinstein, M. L., Rait, M. A., & Prochaska, J. J. (2014). Frequent Marijuana Use is Associated with Greater Nicotine Addiction in Adolescent Smokers. Drug and Alcohol Dependence, 141, 159. https://doi.org/10.1016/J.DRUGALCDEP.2014.05.015
