Cannabis Is Not Doping

Introduction

The recreational and therapeutic use of cannabis is a social polemic. These controversies stand out in sports with renowned athletes and traditional and social media coverage. Nowadays, many athletes are digital influencers who advocate medical cannabis, often through personal stories about the use of the plant. However, the World Anti-Doping Agency (WADA) prohibited the use of cannabinoids during competitions since its foundation in 2004. Ten years ago, the group of Rabin ¹ presented a perspective on the use of cannabis in sports that still influences the WADA's current prohibitive position.

The restrictive conclusion at the time was based on the (1) global illegality of cannabis (and phytocannabinoids), with emphasis on Δ ⁹ -THC, and (2) lack of knowledge about their effects on exercise physiology. ¹ This position should be discussed and revised in the face of new scientific knowledge and social changes regarding the actual therapeutic and recreational use of cannabis.

The WADA uses three criteria to classify a method or substance as doping: (1) ergogenicity, that is, enhancement of athletic performance; (2) risk to the athlete's health, and (3) violation of the spirit of the sports following its World Anti-Doping Code. ² Two criteria configure doping, even if the substance is not ergogenic. Thus, the WADA removed CBD from the banned list in 2018 due to its safety and therapeutic benefits.^3–5 However, cannabis, other phytocannabinoids, and synthetic cannabinoids remain on the 2023 banned list as recommended by the WADA List Expert Advisory Group. ⁶

Even so, some discreet advances have been observed. In 2021, the 1-month suspension (before 2 or 4 years) was lifted for Δ ⁹ -THC as a substance of abuse in the code, guaranteeing out-of-competition use unrelated to sports performance (World Anti-Doping Agency ⁶ ). During competitions, Δ ⁹ -THC at high urinary concentrations of >150 ng/mL is prohibited during competitions; before 2013, the threshold was 15 ng/mL.

However, maintaining cannabis on the WADA prohibited list remains contradictory, as it does not meet the minimum criteria for doping substances. First, cannabis and Δ ⁹ -THC do not increase performance in exercise and sports; that is, they are not ergogenic.^7–12 Second, there is no evidence of health damage to the athletes after 25 years of prohibition, even with increased use among athletes. Third, the spirit of sports is moral and legal policing, which is not within the purview of the International Olympic Committee (IOC) and WADA. The three subsections hereunder discuss this viewpoint.

Ergogenicity: Cannabis Does Not Improve Physical Performance

No evidence demonstrated an increase in sports performance induced by cannabis and Δ ⁹ -THC. Δ ⁹ -THC is a partial agonist of CB₁ receptors (CB₁R, Ki=5–81 nM) in the central nervous system, adipocytes, and muscles. The muscle endocannabinoid (eCB) system is plastic to physical training^13,14 that aims to (1) improve physical performance and (2) prevent athlete injuries. The principles of physical training were coined at the Russian State University of Physical Education in the 1950s by Professor Lev Matveev (1924–2006): ¹⁵ overload (primary), specificity, and individuality, among others.

Skeletal musculature, 30–40% of body mass in humans, is the primary internal force of voluntary movements, significantly activated during exercise that requires good metabolism of ATP regeneration (anaerobic and aerobic) and heat production. Muscles are implicitly involved in energy metabolism and thermoregulation. Likewise, CB₁R regulates energy metabolism through appetite and fuel distribution and usage. ¹⁶

Skeletal muscles participate in the eCB system with cannabinoid receptors (CB₁R and CB₂R), enzymes for the synthesis (N-acyl phosphatidylethanolamine-selective phospholipase D [NAPE–PLD], diacylglycerol lipase α and β [DAGL-α and DAGL-β]) and degradation (fatty acid amide hydrolase [FAAH] and monoacylglycerol lipase [MAGL]) of eCBs.^{13,14,17–20} Most muscle CB₁R is in the mitochondria (mtCB₁R).^16,21

CB₁Rs are in the Z line and mitochondria of skeletal muscles.^14,16,19,21 CB₁R activation inhibits Ca⁺² release by the sarcoplasmic reticulum pump, ¹⁹ whereas mtCB₁R inhibits mitochondrial respiration ²¹ without impairing muscle performance, without ergolytic effects, the opposite of ergogenicity. In contrast, CB₁R antagonism and gene silencing are ergogenic. CB₁R antagonist AM251 and CB₁R knockout (CB₁RKO) increase the number and size (cross-sectional area) of muscles—muscle hypertrophy. ²²

In addition, CB₁RKO releases more myokine interleukin-6 (IL-6) and has a more excellent muscle activity of AKT, MAPK, enolase 3 (Eno3), pyruvate kinase M2, and pyruvate dehydrogenase E1 subunit alpha 1 (PDAH1) that increase pyruvate synthesis and potentiate mitochondrial function, increasing endurance performance in mice.^16,21 Along the same lines, the CB₁R antagonist Rimonabant (SR141716) increases glucose uptake, AMPK activity, and fatty acid β-oxidation.^23–25

This evidence associates CB₁R with the biology of slow oxidative muscle fibers, activated during prolonged low–moderate-intensity exercise (or endurance), which increases eCB concentrations in the postexercise recovery phase.^18,20,26,27 Acute exercise decreases FAAH and MAGL muscle activity and eCB degradation. ¹³ Physical training also increases muscle NAPE–PLD activity. ¹³ This subjective phenomenon, known as runners high,^27,28 is associated with rewards, well-being, anxiety reduction, and peace of mind after aerobic physical activity.

Fun and joy are essential values in the spirit of sports following the WADA antidoping code. ² Bryan's group ²⁹ demonstrated that most adults (81.7%) endorse cannabis use during exercise to improve enjoyment (70.7%) during physical activity and postworkout recovery (77.6%) and less often motivation (51.8%) to exercise. Likewise, Copriviza's group ³⁰ also highlighted enjoyment during exercise (65%) and improved focus/concentration (66%) and mind–body connection (65%). Few felt ergogenic effects. ²⁹ These are the subjective effects of cannabis during exercise; however, the literature has also not demonstrated the ergogenic effects of cannabis on gold physiological (objective) performance indices.

A systematic review (articles up to 2020) by Sarris and colleagues ⁹ did not detect differences in the primary markers of physical performance during exercise: maximum oxygen uptake (V̇O₂max) and power. The Hannah BHKin group ¹¹ also showed no differences in the vital signs, pulmonary measures, physical work capacity, grip strength, and exercise duration. Recently, a low Δ ⁹ -THC dose (10 mg) did not change exercise performance or physiology (maximum and submaximal V̇O₂, respiratory rate, respiratory exchange ratio, and blood lactate levels) during cycle ergometer exercise in active subjects, ⁷ as initially observed by Jacobs and colleagues. ¹⁰

Finally, knowledge from the past two decades has advanced to describe that CB₁R agonism is neither ergogenic nor ergolytic. The human body adapts to exercise by decreasing eCB degradation and CB₁R expression in young muscles. Thus, cannabis and Δ ⁹ -THC do not fulfill the ergogenicity criterion of the WADA antidoping code. ² The ergogenic criterion should be mandatory for classifying a method or substance as doping.

This evidence was built in a laboratory with young, physically active, and healthy individuals. Studies on the effect of cannabis in sports are limited, particularly in elite sports, where athletes compete in world championships and Olympic and Paralympic games. WADA restrictions limit these studies and advances in knowledge.

Cannabis: Athletes' Health Risks Are Overestimated—Benefits Were Ignored

Health risks occur with prolonged and heavy abuse of cannabis, such as breathing problems, mental health issues, impaired cognitive function, and addiction.^31–34 Understanding an elite athlete in this situation of cannabis abuse is difficult, which is incompatible with the physical and mental demands of world championships and the (Para)Olympic games. Concerns about the use of cannabis in younger athletes should be addressed in awareness campaigns.

The physiological impact of cannabis and Δ ⁹ -THC on acute exercise is overestimated for athletes. THC has a positive chronotropic effect (an 18% increase in heart rate [HR])^10,35 with increased cardiac output (HR×stroke volume) ³⁶ while limiting cardiac O₂ consumption in individuals with heart disease. ³⁷ Only in cardiac patients does Δ ⁹ -THC precipitate angina at low exercise loads.^38,39 Electrocardiographic changes were minimal. ⁴⁰ These cardiovascular effects are not associated with poor health in healthy young individuals. ³⁶

Moreover, exercise-induced cardioprotection has the opposite effect: a negative chronotropic effect (lower HR during similar exercise loads) ⁴¹ and a positive inotropic effect (greater force of myocardial contraction during similar exercise loads). ⁴² In the past two decades, there have been no reports of cardiac events in athletes associated with the use of cannabis. Awareness campaigns could quickly educate athletes about regular cardiac evaluations, which already exist in this audience.

A higher accident risk was also an overestimated assumption based on driving impairments in cannabis users.^43,44 However, after two decades, there is no evidence pointing to an increase in accidents in sports, with only one study reporting an increase in bicycle crashes (not cycling) without differences in the severity of injuries, ⁴⁵ even with the increase in cannabis use by elite athletes.^46,47

Little known, Δ ⁹ -THC has positive effects on athletes' health. Cannabis induces bronchodilation, ⁸ and Δ ⁹ -THC readily reverses exercise-induced bronchospasm, a limiting factor for asthmatic athletes. ⁴⁸ β₂-adrenergic agonist bronchodilators are first-line drugs for asthma and chronic obstructive pulmonary disease (COPD). These β₂ agonists are prohibited at all times (training and competition) by the WADA (Substance No. 3 on the banned list), ⁶ even if the ergogenic evidence in nonasthmatics is refuted,^49–51 as for cannabis.

However, there are apparent exceptions to allow therapeutic use by athletes with asthma or COPD, such as inhaled salbutamol (maximum 1,600 μg/day in divided doses of <800 μg/8 h), formoterol (maximum 54 μg/day), salmeterol (maximum 200 μg/day), and vilanterol (maximum 25 μg/day). ⁶ Thus, the bronchodilator and nonergogenic effects of Δ ⁹ -THC and beta seem similar and may benefit athletes with asthma in performance sports.

Moreover, elite athletes are vulnerable to mental health problems, with significant anxiety/depression^52,53 and precompetition poor sleep. ⁵⁴ Classically, psychotropics treat these conditions, such as neurotransmitter reuptake inhibitors (e.g., fluoxetine and duloxetine), tricyclic antidepressants (e.g., amitriptyline and imipramine), monoamine oxidase enzyme inhibitors (e.g., phenelzine), benzodiazepines (e.g., diazepam and clonazepam), nonbenzodiazepine anxiolytics (e.g., buspirone), and atypical antidepressants (e.g., bupropion). We treated sadness with these drugs.

Athletes look to cannabis with another perspective on mental health: fun and enjoyment.^29,30 Similar to any medicine (e.g., psychotropics), cannabis has (short-term) adverse effects, such as dizziness, dry mouth, nausea, fatigue, somnolence, euphoria, vomiting, disorientation, drowsiness, confusion, loss of balance, and hallucination. ⁵⁵ These adverse effects contribute to classifying cannabinoids (except for CBD) as doping during competitions. However, psychotropic drugs have serious side effects, such as nausea, insomnia or drowsiness, dizziness, dry mouth, constipation, increased blood pressure, weight gain, libido modification, headache, nervousness, confusion, dependence, potential withdrawal, and increased risk of suicide.

The WADA prohibits none of these antidepressants and anxiolytic drugs. Even though bupropion is ergogenic,^56,57 it is not prohibited by the WADA but is included in the substance monitoring program. The same occurs with caffeine, nicotine, phenylephrine, phenylpropanolamine, pipradrol, and synephrine.

The Spirit of the Sports Clause Is Vague and Ineffective in Detecting Doping

The WADA Ethics Expert Advisory Group recommended keeping all cannabinoids, except for CBD, on the 2023 prohibited list (in-competition), according to their “Guiding Values in Sport and Anti-Doping.” ⁵⁸ This polemical ethics guide protects “certain values” of sports, such as fairness and justice, the risk of harm, proportionality, science-based, transparency, and education/public/athlete engagement. ⁵⁸ However, departing from the very values of transparency, the WADA does not report the ethical value infringed by cannabis exclusively during competitions. Cannabis is allowed in preparatory and regenerative training, “the risk of harm disappears.”

The IOC's attention to cannabis started in 1989, not before then. The start of the analysis of cannabis from 1988 tested positive for several athletes. This new information concerned Britain's sports council, its ethics and antidoping directorate, who argued that cannabis was cheating and harmful to the image of sports. ⁵⁹ In 2003, the “spirit of sports” clause was added to the antidoping code, influenced by political and social factors of the time, often influenced by crises and scandals, with the Ben Johnson case in the 1988 Summer Olympics. ⁶⁰

The cannabis crisis came with Canadian snowboarder Ross Rebagliati at the 1988 Winter Olympics. Ross was the first gold medalist in the giant slalom and showed 17.8 ng/mL of the THC metabolite 11-nor-9-carboxy-delta-(9)-tetrahydrocannabinol (THC-COOH) in the urine, above the 15 ng/mL limit set by the International Ski Federation. The IOC executive board voted 3-2 for the disqualification and withdrawal of the medal, restored 2 days later due to the Canadian Olympic Association's appeal, as the IOC did not officially ban cannabis. Two months later, the IOC started classifying cannabis as doping. The New York Times dubbed this decision the “Ross Rebagliati Rule.” ⁶¹

The urinary THC-COOH threshold was raised to 150 ng/mL in 2013, which is insufficient to avoid the distortions of any moral closure in the history of humanity. More recently, U.S. sprinter (100 and 200 m) Sha'Carri Richardson tested positive for THC-COOH after her victory in the U.S. Olympic Trials final. The U.S. antidoping agency suspended the athlete for a month and prevented her from participating in the Summer Olympic Games in 2020.

Sha'Carri acknowledged using cannabis for mental health problems due to the psychological pressure to qualify for the Olympics while dealing with her mother's death. In 2020, the WADA suspended 42 athletes for using cannabis during competition, ⁶² a nonergogenic substance with limited health risks similar to other released substances, such as caffeine, nicotine (tobacco), and alcohol. Even the caffeine in coffee and chocolate has had a bad time with the WADA.

The new subjective “spirit of sports” clause in 2003 distorted the technical and original criteria of ergogenicity and the risk to the athletes' health. This confusion explains why common individuals cannot understand why cannabis configures doping. This millennial plant used since ancient China (2700 BCE), Persia (2000 BCE), and Sumeria (1800 BCE) ⁶³ is antagonistic to cheating anabolic steroids, erythropoietin (EPO), and stimulants. Some members of the IOC medical committee itself reinforced these inconsistencies—Prince Alexandre de Mérode augmented that cannabis does not affect sports performance, and Professor Arnold Beckett declared that if we police the social aspects of drugs, the WADA is not doing its job. ⁶⁴

The values of “fairness and fairness” apply to the ergogenic features that cannabis does not have. “Health risks,” a redundant position (second criterion) criticized by sports experts, have weak foundations, as presented in the previous subsection. “Proportionality” is not observed as the WADA's antidoping objectives conflict with violating athletes' privacy. The antidoping stance for cannabis also lacks “scientific foundations,” as discussed in the two previous subsections. The WADA is not supposed to legally and morally police society, including athletes. ⁶⁵

The legality of cannabis is the sovereign responsibility of the States and Nations. Canada, Georgia, Malta, Mexico, South Africa, Thailand, and Uruguay, plus 21 states, 2 territories, and the District of Columbia in the United States and the Australian Capital Territory in Australia legalized the recreational use of cannabis.

The first ergogenicity criterion should be mandatory for the doping classification. ⁶⁵ Athletes use cannabis for medicinal and recreational purposes; it does not pay to win medals, and there is no dishonesty in this case. What is wrong with seeking health care? Elite athletes are vulnerable to mental health problems recognized by the IOC ⁶⁶ related to sports (e.g., injuries, training, and burnout) and nonsports factors (e.g., family death) ⁵² as they also have a private life outside of training and competitions, as in the case of Sha'Carri Richardson. U.S. gymnast Simone Biles urged this mental health debate in the recent 2021 Summer Olympics (postpandemic).

Moreover, what is wrong with having fun? Athletes use cannabis for fun and enjoyment,^29,30 essential elements of the very spirit of sports present in the WADA antidoping code. ² With all due respect to Professor Lev Matveev, I propose to add one more principle of physical training, the principle of fun and joy, perhaps something not well regarded at the time of the original principles in the austere postwar Soviet Union of the 1950s. The concept of “no pain, no gain” must be reconsidered regarding athletes' humanity and (physical and mental) health (mens sana in corpore sano). Athletes are the spirit of sports.

The most important thing is not to win but to participate, as recommended by Coubertin at the 1908 Summer Olympics. Some hockey and basketball sports leagues have stopped policing cannabis and athletes. The National Hockey League (NHL) does not ban cannabis and does not punish athletes for testing positive for this substance. The National Basketball Association (NBA) will follow suit in the 2023–2024 season.

Conclusion

Modern society's relationship with cannabis has matured, and its use by adult athletes should no longer be demonized. This perspective piece recommends that the WADA permanently removes cannabis and phytocannabinoids from the list of prohibited substances during competitions to benefit elite adult athletes and sports. This opinion does not apply to synthetic cannabinoids.