Cannabis: Exercise performance and sport. A systematic review

Performance-Enhancing Drugs in Healthy Athletes: An Umbrella Review of Systematic Reviews and Meta-analyses

CONTEXT

Many clinicians, trainers, and athletes do not have a true understanding of the effects of commonly used performance-enhancing drugs (PEDs) on performance and health.

OBJECTIVE

To provide an evidence-based review of 7 commonly used pharmacological interventions for performance enhancement in athletes.

DATA SOURCES

PubMed and Scopus databases were searched on April 8, 2022.

STUDY SELECTION

Systematic reviews (SRs) and meta-analyses (MAs) assessing the performance-enhancing effects of the following interventions were included: androgenic anabolic steroids (AAS), growth hormone (GH), selective androgen receptor modulators (SARMs), creatine, angiotensin-converting enzyme (ACE)-inhibitors, recombinant human erythropoietin (rHuEPO), and cannabis.

STUDY DESIGN

Umbrella review of SRs and MAs.

LEVEL OF EVIDENCE

Level 4.

DATA EXTRACTION

Primary outcomes collected were (1) body mass, (2) muscle strength, (3) performance, and (4) recovery. Adverse effects were also noted.

RESULTS

A total of 27 papers evaluating 5 pharmacological interventions met inclusion criteria. No studies evaluating SARMs or ACE-inhibitors were included. AAS lead to a 5% to 52% increase in strength and a 0.62 standard mean difference in lean body mass with subsequent lipid derangements. GH alters body composition, without providing a strength or performance benefit, but potential risks include soft tissue edema, fatigue, arthralgias, and carpel tunnel syndrome. Creatine use during resistance training can safely increase total and lean body mass, strength, and performance in high-intensity, short-duration, repetitive tasks. Limited evidence supports rHuEPO benefit on performance despite increases in both VO2max and maximal power output, and severe cardiovascular risks are documented. Cannabis provides no performance benefit and may even impair athletic performance.

CONCLUSION

In young healthy persons and athletes, creatine can safely provide a performance-enhancing benefit when taken in controlled doses. AAS, GH, and rHuEPO are associated with severe adverse events and do not support a performance benefit, despite showing the ability to change bodily composition, strength, and/or physiologic measures. Cannabis may have an ergolytic, instead of ergogenic, effect.

Effect of Stanozolol and/or Cannabis Abuse on Hypertrophic Mechanism and Oxidative Stress of Male Albino Rat Cardiac Tissue in Relation to Exercise: A Sport Abuse Practice

Adolescents commonly co-abuse many drugs including anabolic androgenic steroids either they are athletes or non-athletes. Stanozolol is the major anabolic used in recent years and was reported grouped with cannabis. The current study aimed at evaluating the biochemical and histopathological changes related to the hypertrophic effects of stanozolol and/or cannabis whether in condition of exercise practice or sedentary conditions. Adult male Wistar albino rats received either stanozolol (5 mg/kg, s.c), cannabis (10 mg/kg, i.p.), and a combination of both once daily for two months. Swimming exercise protocol was applied as a training model. Relative heart weight, oxidative stress biomarkers, cardiac tissue fibrotic markers were evaluated. Left ventricular morphometric analysis and collagen quantification was done. The combined treatment exhibited serious detrimental effects on the heart tissues. It increased heart tissue fibrotic markers (Masson's trichrome stain (p < 0.001), cardiac COL3 (p < 0.0001), and VEGF-A (p < 0.05)), lowered heart glutathione levels (p < 0.05) and dramatically elevated oxidative stress (increased malondialdehyde (p < 0.0001) and 8-OHDG (p < 0.0001)). Training was not ameliorating for the observed effects. Misuse of cannabis and stanozolol resulted in more hypertrophic consequences of the heart than either drug alone, which were at least largely assigned to oxidative stress, heart tissue fibrotic indicators, histological alterations, and morphometric changes.

Cardiotoxic effects of common and emerging drugs: role of cannabinoid receptors

Drug-induced cardiotoxicity has become one of the most common and detrimental health concerns, which causes significant loss to public health and drug resources. Cannabinoid receptors (CBRs) have recently achieved great attention for their vital roles in the regulation of heart health and disease, with mounting evidence linking CBRs with the pathogenesis and progression of drug-induced cardiotoxicity. This review aims to summarize fundamental characteristics of two well-documented CBRs (CB1R and CB2R) from aspects of molecular structure, signaling and their functions in cardiovascular physiology and pathophysiology. Moreover, we describe the roles of CB1R and CB2R in the occurrence of cardiotoxicity induced by common drugs such as antipsychotics, anti-cancer drugs, marijuana, and some emerging synthetic cannabinoids. We highlight the 'yin-yang' relationship between CB1R and CB2R in drug-induced cardiotoxicity and propose future perspectives for CBR-based translational medicine toward cardiotoxicity curation and clinical monitoring.

Cannabis containing THC impairs 20-min cycling time trial performance irrespective of the method of inhalation

Herein, we examine the human exercise response following cannabis inhalation, taking into consideration varied cannabinoid concentrations and different inhalation methods. A semirandomized crossover study design was used, with measures of perceived exertion and physiological responses to submaximal and maximal exercise. Participants (n = 14, 9 males 5 females) completed exercise after 1) smoking Δ-9-tetrahydrocannabinol (THC)-predominant cannabis (S-THC), 2) inhaling aerosol (vaporizing) from THC-predominant cannabis (V-THC), 3) inhaling aerosol from cannabidiol (CBD)-predominant cannabis (V-CBD), or 4) under control conditions. All exercise was performed on a cycle ergometer, with submaximal testing performed at 100 W followed by an evaluation of maximal exercise performance using an all-out 20-min time trial. Metabolism was characterized via the analysis of expired gases while subjective ratings of perceived exertion (RPE) were reported. During submaximal cycling, heart rate was higher during S-THC and V-THC compared with both control and V-CBD (all P < 0.02). During maximal exercise, V̇e was lower in V-THC compared with control, S-THC, and V-CBD (all P < 0.03), as was S-THC compared with control (P < 0.05). Both V̇o2 and RPE were similar between conditions during maximal exercise (both P > 0.1). Mean power output during the 20-min time trial was significantly lower in the S-THC and V-THC conditions compared with both control and V-CBD (all P < 0.04). Cannabis containing THC alters the physiological response to maximal and submaximal exercise, largely independent of the inhalation method. THC-containing cannabis negatively impacts vigorous exercise performance during a sustained 20-min effort, likely due to physiological and psychotropic effects. Inhalation of cannabis devoid of THC and primarily containing CBD has little physiological effect on the exercise response or performance.NEW & NOTEWORTHY Inhalation of cannabis containing THC alters physiological responses to both submaximal and maximal exercise and reduces mean power output during a 20-min time trial, regardless of whether it is inhaled as smoke or aerosol. In contrast, cannabis devoid of THC and predominantly containing CBD has no effect on physiological responses to exercise or performance.

Cannabis Is Not Doping

The World Anti-Doping Agency (WADA) classifies cannabis, all phytocannabinoids, and synthetics as doping, except for CBD. For agency, a method for doping substance must meet two criteria: performance enhancement (ergogenicity), health risk, or violation of the spirit of sports. Cannabis is neither ergogenic nor ergolytic (performance worsens), and the health risks for athletes are overestimated after 20 years of research. The significant problem remains in the complex (and difficult interpretation) definition of the spirit of sports, which transcends the objectives of sports excellence (performance and injury prevention) for moral policing. This perspective presents an evidence-based counterargument recommending the removal of cannabis and phytocannabinoids from the WADA Prohibited List.

The impact of aerobic exercise training on cognitive function and gut microbiota in methamphetamine-dependent individuals in the community

OBJECTIVE

This study aimed to investigate the impact and mechanism of gut microbiota on the enhancement of cognitive function in methamphetamine (MA)-dependent individuals during aerobic exercise training.

METHODS

A total of sixty-four MA-dependent individuals were randomly assigned to either an aerobic exercise training group (DK, n = 32) or a conventional rehabilitation group (CK, n = 32). After an eight-week intervention, the participants' working memory and inhibition ability were assessed using the Stroop paradigm and Go/NoGo paradigm, respectively. Gut microbiota composition was analyzed using high-throughput sequencing.

RESULTS

1) Eight weeks of aerobic exercise training significantly improved the working memory and inhibition ability of MA-dependent individuals (P < 0.05). 2) Following the intervention, the DK group exhibited significantly higher levels of Lactobacillus, Lactococcus lactis, Prevotellaceae, and Ruminococcaceae compared to the CK group. Conversely, the DK group demonstrated significantly lower levels of Desulfovibrio and Akkermansia compared to the CK group. Furthermore, the DK group showed significantly increased metabolic pathways associated with d-Glutaralate and d-Galactate Degradation, as well as the Alanine, aspartate, and glutamate metabolism pathway, compared to the control group. 3) Cognitive function related to MA addiction positively correlated with Bifidobacterium, Dialister, and Adlercreutzia, while negatively correlated with Enterobacteria, Bacillus cereus, Catabacter, and Akkermansia.

CONCLUSION

Aerobic exercise training enhances working memory and inhibition ability in MA-dependent individuals, thereby mitigating the detrimental effects of MA addiction on cognitive function. Additionally, analysis of gut microbiota suggests that the modulation of gut microbiota and associated metabolic pathways play a role in regulating the improvement of cognitive function in MA-dependent individuals through exercise.

To Weed or Not to Weed: A Systematic Review Exploring the Potential for Cannabis Use in Cardiovascular Disease, Mental Health and Pain Management

Despite its historical reputation as a substance of abuse, cannabis use has increased following decriminalization efforts in the United States. It has historically garnered a bad reputation as a substance of abuse, but paradoxically is associated with an improved perception of well-being. We were interested in positive cardiovascular outcomes, both positive and negative mental health outcomes and impact on physical activity of cannabis, both recreational and medical. Databases included PubMed, ResearchGate, Cochrane, Science.gov and ScienceDirect. We were interested in cardiovascular, mental health and physical health in our search. Data included articles published during or after 2017. Our studies showed no cardiovascular benefits, increased risk of documented cardiovascular events and increased mortality associated with cannabis use. Physical benefits derived were largely in patients with chronic pain. With regards to mental health, the impact of the drug appears to be both positive and negative, with no clear benefits as a first-line agent. Route of administration appears to have an impact on the overall extent of side effects. Overall, medical cannabis appears to pose an almost negligible side effect profile compared to recreational. Our findings suggest that while cannabis use may offer benefits for chronic pain management, it is associated with increased cardiovascular risks. Further, medical cannabis appears to have a more favorable side effect profile compared to recreational use.

Cannabidiol: Bridge between Antioxidant Effect, Cellular Protection, and Cognitive and Physical Performance

The literature provides scientific evidence for the beneficial effects of cannabidiol (CBD), and these effects extend beyond epilepsy treatment (e.g., Lennox-Gastaut and Dravet syndromes), notably the influence on oxidative status, neurodegeneration, cellular protection, cognitive function, and physical performance. However, products containing CBD are not allowed to be marketed everywhere in the world, which may ultimately have a negative effect on health as a result of the uncontrolled CBD market. After the isolation of CBD follows the discovery of CB1 and CB2 receptors and the main enzymatic components (diacylglycerol lipase (DAG lipase), monoacyl glycerol lipase (MAGL), fatty acid amino hydrolase (FAAH)). At the same time, the antioxidant potential of CBD is due not only to the molecular structure but also to the fact that this compound increases the expression of the main endogenous antioxidant systems, superoxide dismutase (SOD), and glutathione peroxidase (GPx), through the nuclear complex erythroid 2-related factor (Nrf2)/Keep1. Regarding the role in the control of inflammation, this function is exercised by inhibiting (nuclear factor kappa B) NF-κB, and also the genes that encode the expression of molecules with a pro-inflammatory role (cytokines and metalloproteinases). The other effects of CBD on cognitive function and physical performance should not be excluded. In conclusion, the CBD market needs to be regulated more thoroughly, given the previously listed properties, with the mention that the safety profile is a very good one.

Beyond Pain Relief: A Review on Cannabidiol Potential in Medical Therapies

The phytocannabinoid cannabidiol (CBD) is receiving increasing attention due to its pharmacological properties. Although CBD is extracted from Cannabis sativa, it lacks the psychoactive effects of Δ9-tetrahydrocannabinol (THC) and has become an attractive compound for pharmacological uses due to its anti-inflammatory, antioxidant, anticonvulsant, and anxiolytic potential. The molecular mechanisms involved in CBD's biological effects are not limited to its interaction with classical cannabinoid receptors, exerting anti-inflammatory or pain-relief effects. Several pieces of evidence demonstrate that CBD interacts with other receptors and cellular signaling cascades, which further support CBD's therapeutic potential beyond pain management. In this review, we take a closer look at the molecular mechanisms of CBD and its potential therapeutic application in the context of cancer, neurodegeneration, and autoimmune diseases.

Edible marijuana and cycle ergometer exercise

Purpose: There is extensive public and scientific interest in the influence of cannabis and the psychoactive cannabinoid, delta-9-tetrahydrocannabinol (THC), on exercise performance. Unfortunately, recent, up-to-date studies are lacking. The aim of the current study was to address the hypothesis that ingestion of edible marijuana, prior to exercise, would have unfavorable effects on the physiological response to exercise and on exercise performance. Methods: 17 Healthy adult male and female habitual exercisers, who were regular users of cannabis products, were screened for study participation. 10 were enrolled, and data from 9 [8 males, 1 female, aged 25±3 years, with peak oxygen uptake of 56.5±11.7 ml/kg/min (mean ± SD)] were retained. Participation included two exercise sessions, each preceded by self-administration and ingestion of either edible marijuana (containing 10 mg THC) or placebo. Cardio-respiratory responses (via indirect calorimetry) to stationary cycle ergometer exercise (8 min at 50, 100 and 150 W) were recorded before completion of a 20-min Functional Threshold Power test (FTP²⁰) and a sprint test involving maximal effort until volitional fatigue. Results: Edible marijuana increased the concentration of circulating THC and THC metabolites, and evoked sensations of intoxication and altered psychoactive state. Cardio-respiratory responses to staged cycle ergometer exercise were normal and were unaffected by edible marijuana. Compared with placebo, edible marijuana did not influence FTP²⁰ (Placebo 253±75 vs THC: 251±72 W (mean±SD); p > 0.45) or peak power output during the sprint test (Placebo: 710±201 vs. THC: 732±136 W; p = 0.864). Conclusion: 10 mg of THC, when ingested prior to exercise by regular exercisers and habitual users of cannabis, had little effect on the physiological response to standardized cycle ergometer exercise, and was neither ergogenic nor ergolytic.

How and why adults use cannabis during physical activity

BACKGROUND

With increased legalization of cannabis, users are combining cannabis with exercise. The purpose of this study is to understand how and why people use cannabis when participating in physical activity.

METHODS

A convenience sample of cannabis users participated in an anonymous online survey created by the authors regarding exercise habits while under the influence of cannabis, perceived benefits, unanticipated experiences related to cannabis and exercise, and demographics.

RESULTS

One hundred thirty-one respondents (18-55 years) were eligible and began the survey. Nearly 60 physical activities under the influence of cannabis were reported. The most frequently reported modes of exercise included hiking (60%), yoga (58%), and aerobic machines (50%). The primary reasons for using cannabis before exercise were "helping to focus/concentrate" (66%), "helping enjoy the exercise experience" (65%), and "enhancing mind-body-spirit connection" (65%). Thirty-three participants reported "yes" or "maybe" regarding having an experience they "didn't anticipate or desire while exercising under the influence of cannabis."

DISCUSSION

Participants' reasons for exercising with cannabis span the physiological, psychological, neuromotor, and even spiritual domains. However, some reported an undesired experience when pairing cannabis with exercise. While this was an online survey with a small sample size, our results agree with and contribute to the growing research investigating cannabis use and physical activity participation.

CONCLUSION

We found considerable heterogeneity in types of physical activity participation under the influence of cannabis, as well as perceived benefits of use. This study provides directions to further explore the risks and benefits of combining cannabis with physical activity.

Cannabis, cannabidiol and tetrahydrocannabinol in sport: An overview

The World Antidoping Agency now allows cannabidiol (CBD) to be taken in elite sport but has retained all other cannabinoids on its banned list. This, together with liberalisation of cannabis laws have led to an increasing interest in its use in sport. This includes commercial sponsorship of sporting events and highlights the need for accurate information to be readily available to athletes and their advisers. This narrative review confirms that CBD and tetrahydrocannabinol (THC) do not enhance performance. CBD possesses anti-inflammatory and analgesic properties which have not been adequately evaluated in the area of sport. Some formulations of CBD contain THC or other cannabinoids that may result in a positive drug test. This article is protected by copyright. All rights reserved.

Daily Physical Activity, Sedentary Behavior and Alcohol Use in At-Risk College Students

BACKGROUND

The college years present an opportunity to establish health behavior patterns that can track across adulthood. Health behaviors tend to cluster synergistically however, physical activity and alcohol have shown a positive association.

PURPOSE

This study applied a multi-method approach to estimate between- and within-person associations between daily physical activity, sedentary behavior and alcohol use among polysubstance-using college students.

METHODS

Participants were screened for recent binge drinking and either tobacco or cannabis use. They wore an activPAL4 activity monitor and a Secure Continuous Remote Alcohol Monitor continuously in the field for 11 days, and completed daily online questionnaires at the beginning of each day to report previous day physical activity, sedentary behavior, and alcohol consumption.

RESULTS

Participants (N = 58, Mage = 20.5 years, 59% women, 69% White) reported meeting national aerobic physical activity guidelines (75%) and drinking 2-4 times in the past month (72%). On days when participants reported an hour more than usual of daily sedentary behavior, they reported drinking for less time than usual (γ = -.06). On days when participants took 1,000 more steps than usual, the longest episode of continuous transdermal alcohol detection was shorter (γ = -.03).

CONCLUSIONS

Daily physical activity and sedentary behavior were negatively associated with time-based measures of alcohol use with the lowest risk on days characterized by both activity and sedentary behavior. Intensive longitudinal monitoring of time-based processes can provide new insights into risk in multiple behavior change and should be prioritized for future work.

Cannabis and Athletic Performance

Cannabis is widely used for both recreational and medicinal purposes on a global scale. There is accumulating interest in the use of cannabis and its constituents for athletic recovery, and in some instances, performance. Amidst speculation of potential beneficial applications, the effects of cannabis and its two most abundant constituents, delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD), remain largely un-investigated. The purpose of this review is to critically evaluate the literature describing the effects of whole cannabis, THC, and CBD, on athletic performance and recovery. While investigations of whole cannabis and THC have generally shown either null or detrimental effects on exercise performance in strength and aerobic-type activities, studies of sufficient rigor and validity to conclusively declare ergogenic or ergolytic potential in athletes are lacking. The ability of cannabis and THC to perturb cardiovascular homeostasis warrants further investigation regarding mechanisms by which performance may be affected across different exercise modalities and energetic demands. In contrast to cannabis and THC, CBD has largely been scrutinized for its potential to aid in recovery. The beneficial effects of CBD on sleep quality, pain, and mild traumatic brain injury may be of particular interest to certain athletes. However, research in each of these respective areas has yet to be thoroughly investigated in athletic populations. Elucidating the effects of whole cannabis, THC, and CBD is pertinent for both researchers and practitioners given the widespread use of these products, and their potential to interact with athletes' performance and recovery.

Substance Use and Its Impact on Athlete Health and Performance

The pressure to gain mass, power, explosiveness, and endurance and to obtain a performance edge continues to a part of sports. Anabolic agents, including selective androgen receptor modulators along with peptides, hormones, and metabolic modulators, continues to evolve. Methods to promote transcription to modify gene expression are a part of the evolution. In order to monitor and improve doping detection, the Athlete Biological Passport has been created. This article provides an up-to-date review of alcohol, anabolic androgens and related agents, stimulants, opioids, and cannabis and related compounds and their effects on athlete health and performance.

Troubleshooting a Nonresponder: Guidance for the Strength and Conditioning Coach

Ideally an athlete would continue to improve performance indefinitely over time, however improvement slows as the athlete approaches their genetic limits. Measuring performance is complex—performance may be temporarily depressed following aggressive training for multiple reasons, physiological and psychosocial. This reality may be vexing to the strength and conditioning coach, who, as a service provider, must answer to sport coaches about an athlete’s progress. Recently an evaluation mechanism for strength and conditioning coaches was proposed, in part to help coaches establish their effectiveness within the organization. Without formal guidance and realistic expectations, if an athlete is not bigger, leaner, stronger, etc. as a result of training within a specified timeframe, blame is often placed upon the strength and conditioning coach. The purpose of this article is to explore possible causes of what may be perceived as athlete non-responses to training and to provide guidance for the coach on how to handle those issues within their domain. A process of investigation is recommended, along with resources to assist coaches as they consider a broad range of issues, including enhancing existing testing methods, improving athlete behaviors, and adjusting processes designed to bring about performance improvement.

The relationships between marijuana use and exercise among young and middle-aged adults

As decriminalization, increased access, and decreased perception of risk spurs the popularity of medical and recreational marijuana, more information is needed on possible links between marijuana use and social determinants of health. The goal of this study was to assess the relationships between marijuana use and exercise. Data sources included the two most recent waves of the National Longitudinal Study of Adolescent to Adult Health (Wave IV, 2008-2009; N = 14,784 and Wave V, 2016-2018; N = 12,043). The exercise variables included any form of exercise/sport during the past 7 days and the number of days participating in each of 7 types of exercise/sport. Marijuana-use variables comprised any current use and frequency of use during the past 30 days. Both fixed-effects and random-effects models were estimated with numerous control variables, along with binary and count measures of exercise. Results show that, particularly for fixed-effects models, marijuana use is not significantly related to exercise, counter to conventional wisdom that marijuana users are less likely to be active. Indeed, the only significant estimates suggest a positive relationship, even among heavier users during the past 30 days. These findings are at odds with much of the existing literature, which generally shows a negative relationship between marijuana use and exercise. As additional states legalize the medicinal and recreational use of marijuana, perhaps its impact on exercise, one of the leading social determinants of health, is not necessarily a primary concern.

Cannabis and exercise: Effects of Δ9-tetrahydrocannabinol on preference and motivation for wheel-running in mice

Recent surveys have revealed close links between cannabis and exercise. Specifically, cannabis usage before and/or after exercise is an increasingly common habit primarily aimed at boosting exercise pleasure, motivation, and performance whilst facilitating post-exercise recovery. However, whether these beliefs reflect the true impact of cannabis on these aspects of exercise is unknown. This study has thus examined the effects of cannabis' main psychoactive ingredient, namely Δ⁹-tetrahydrocannabinol (THC), on (i) mouse wheel-running preference and performance and (ii) running motivation and seeking behaviour. Wheel-running preference and performance were investigated using a T-maze with free and locked wheels located at the extremity of either arm. Running motivation and seeking were assessed by a cued-running operant task wherein wheel-running was conditioned by nose poking. Moreover, because THC targets cannabinoid type 1 (CB₁) receptors, i.e. receptors previously documented to control running motivation, this study also assessed the role of these receptors in running preference, performance, and craving-like behaviour. Whilst acute blockade or genetic deletion of CB₁ receptors decreased running preference and performance in the T-maze, THC proved ineffective on either variable. The failure of THC to affect running variables in the T-maze extended to running motivation, as assessed by cued-running under a progressive ratio (PR) reinforcement schedule. This ineffectiveness of THC was not related to the treatment protocol because it successfully increased motivation for palatable food. Although craving-like behaviour, as indexed by a cue-induced reinstatement of running seeking, was found to depend on CB₁ receptors, THC again proved ineffective. Neither running motivation nor running seeking were affected when CB₁ receptors were further stimulated by increasing the levels of the endocannabinoid 2-arachidonoylglycerol. These results, which suggest that the drive for running is insensitive to the acute stimulation of CB₁ receptors, raise the hypothesis that cannabis is devoid of effect on exercise motivation. Future investigation using chronic administration of THC, with and without other cannabis ingredients (e.g. cannabidiol), is however required before conclusions can be drawn.

A systematic review of physical activity, sedentary behavior, and substance use in adolescents and emerging adults

The transition from adolescence into emerging adulthood is marked by changes in both physical activity and substance use. This systematic review characterized associations between movement behaviors (physical activity, sedentary behavior) and frequently used substances (alcohol, cannabis) among adolescents and emerging adults to inform lifestyle interventions that target multiple behavior change outcomes. This systematic review was guided by PRISMA. Electronic databases of PubMed, PsycINFO, and Web of Science were searched from inception through June 25, 2019. The search was designed to identify empirical studies reporting an association between physical activity or sedentary behavior and alcohol or cannabis, with search criteria determining eligibility based on several sampling characteristics (e.g., participants under 25 years of age). After identifying and screening 5,610 studies, data were extracted from 97 studies. Physical activity was positively associated with alcohol use among emerging adults, but the literature was mixed among adolescents. Sedentary behavior was positively associated with alcohol and cannabis use among adolescents, but evidence was limited among emerging adults. Self-report measures were used in all but one study to assess these behaviors. Physical activity is linked to greater alcohol use among emerging adults. Whereas existing studies demonstrate that sedentary behavior might serve as a risk marker for alcohol and cannabis use among adolescents, additional primary research is needed to explore these associations in emerging adults. Future work should also use device-based measures to account for timing of and contextual features surrounding activity and substance use in these populations.

Chronic cannabis consumption and physical exercise performance in healthy adults: a systematic review

OBJECTIVE

The effects of chronic cannabis consumption on physiological parameters of athletic performance are investigated to determine whether chronic cannabis consumption negatively affects athletic performance; improves performance, potentially via enhanced recovery; or has no effect at all.

METHODS

A systematic review of the literature (cross-sectional, longitudinal, and intervention studies) concerning the effects of cannabis consumption on sports performance outcomes, e.g. VO2Max (maximal oxygen uptake), PWC (physical work capacity) up to January 2020 was conducted using the PubMed, CINAHL, Medline, PsycArticles, PsycInfo, SPORTDiscus, Psychology and Behavioural Sciences Collection, and Health Source: Nursing/Academic Edition databases. After screening and additional forward searching, four articles were found to fit the inclusion criteria.

RESULTS

Resting heart rate was the only physiological measure that significantly differed between groups, and only in one of the four studies included herein. The strongest predictors of athletic performance (VO2Max and PWC) were not found to be significantly different between groups in any of the included studies. Chronic cannabis consumption had no significant effect on athletic performance. The included studies did not assess other elements, such as recovery or endurance.

CONCLUSION

No evidence exists for ergogenic or ergolytic effects from chronic cannabis consumption. In some sports, advantages may plausibly be conveyed by psychotropic enhancement or pain reduction. Further research (particularly longitudinal or interventional studies) is required to determine whether cannabis, or constituents thereof, may provide indirect supplemental benefits to athletes.

Acute effects of cannabis consumption on exercise performance: a systematic and umbrella review

INTRODUCTION

The goal of this systematic and umbrella review was to regroup all systematic reviews, non-systematic reviews and all original articles into one convenient publication that would facilitate the theoretical and applied scientific investigations directed on cannabis consumption and exercise performance, to update current findings on the matters, and assess evidence quality.

EVIDENCE ACQUISITION

The systematic review was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) method. A computer-based systematic search was conducted in September 2019 through the Pubmed, Scopus and SPORTDiscus databases. The reliability of the systematic search was assured by having the article selection process entirely repeated by a second author. Strength of evidence of the selected articles was assesses using a modified version of the Downs and Black Checklist.

EVIDENCE SYNTHESIS

The systematic search yielded a total of 8 peer-reviewed publications as well as 10 literature reviews. Results show that cannabis consumption prior to exercise induces decrements in performance (reduced ability to maintain effort, physical/maximal work capacity), undesired physiological responses (increased heart and breathing rate as well as myocardial oxygen demand) and neurological effects on balance (increased sway).

CONCLUSIONS

Based on the articles included in this review, the authors conclude 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. Further research should mimic modern THC dosage (150 mg).

Cannabidiol and Sports Performance: a Narrative Review of Relevant Evidence and Recommendations for Future Research

Cannabidiol (CBD) is a non-intoxicating cannabinoid derived from Cannabis sativa. CBD initially drew scientific interest due to its anticonvulsant properties but increasing evidence of other therapeutic effects has attracted the attention of additional clinical and non-clinical populations, including athletes. Unlike the intoxicating cannabinoid, Δ9-tetrahydrocannabinol (Δ9-THC), CBD is no longer prohibited by the World Anti-Doping Agency and appears to be safe and well-tolerated in humans. It has also become readily available in many countries with the introduction of over-the-counter "nutraceutical" products. The aim of this narrative review was to explore various physiological and psychological effects of CBD that may be relevant to the sport and/or exercise context and to identify key areas for future research. As direct studies of CBD and sports performance are is currently lacking, evidence for this narrative review was sourced from preclinical studies and a limited number of clinical trials in non-athlete populations. Preclinical studies have observed robust anti-inflammatory, neuroprotective and analgesic effects of CBD in animal models. Preliminary preclinical evidence also suggests that CBD may protect against gastrointestinal damage associated with inflammation and promote healing of traumatic skeletal injuries. However, further research is required to confirm these observations. Early stage clinical studies suggest that CBD may be anxiolytic in "stress-inducing" situations and in individuals with anxiety disorders. While some case reports indicate that CBD improves sleep, robust evidence is currently lacking. Cognitive function and thermoregulation appear to be unaffected by CBD while effects on food intake, metabolic function, cardiovascular function, and infection require further study. CBD may exert a number of physiological, biochemical, and psychological effects with the potential to benefit athletes. However, well controlled, studies in athlete populations are required before definitive conclusions can be reached regarding the utility of CBD in supporting athletic performance.

The blind men and the elephant: Systematic review of systematic reviews of cannabis use related health harms

Cannabis is the third most used psychoactive substance worldwide. The legal status of cannabis is changing in many Western countries, while we have very limited knowledge of the public health impact of cannabis-related harms. There is a need for a summary of the evidence of harms and risks attributed to cannabis use, in order to inform the definition of cannabis risky use. We have conducted a systematic review of systematic reviews, aiming to define cannabis-related harms. We included systematic reviews published until July 2018 from six different databases and following the PRISMA guidelines. To assess study quality we applied the AMSTAR 2 tool. A total of 44 systematic reviews, including 1,053 different studies, were eligible for inclusion. Harm was categorized in three dimensions: mental health, somatic harm and physical injury (including mortality). Evidence shows a clear association between cannabis use and psychosis, affective disorders, anxiety, sleep disorders, cognitive failures, respiratory adverse events, cancer, cardiovascular outcomes, and gastrointestinal disorders. Moreover, cannabis use is a risk factor for motor vehicle collision, suicidal behavior and partner and child violence. Cannabis use is a risk factor for several medical conditions and negative social consequences. There is still little data on the dose-dependency of these effects; evidence that is essential in order to define, from a public health perspective, what can be considered risky use of cannabis. This definition should be based on quantitative and qualitative criteria that informs and permits the evaluation of current approaches to a regulated cannabis market.

Current Trends in Ultramarathon Running

Exercise is universally recognized for its health benefits and distance running has long been a popular form of exercise and sport. Ultramarathons, defined as races longer than a marathon, have become increasingly popular in recent years. The diverse ultramarathon distances and courses provide additional challenges in race performance and medical coverage for these events. As the sport grows in popularity, more literature has become available regarding ultramarathon-specific illnesses and injuries, nutrition guidelines, psychology, physiologic changes, and equipment. This review focuses on recent findings and trends in ultramarathon running.

Sport-Specific Use of Doping Substances: Analysis of World Anti-Doping Agency Doping Control Tests between 2014 and 2017

Background: In recent years, there has been a solid effort across all sports organizations to reduce the prevalence and incidence of doping in sport. However, the efficacy of current strategies to fight against doping might be improved by using anti-doping polices tailored to the features of doping in each sport. Objectives: The aim of this investigation was to analyze the substances more commonly found in doping control tests in individual and team sports. Material and Methods: The publicly accessible Testing Figures Reports made available by the World Anti-Doping Agency, were analyzed from 2014 to 2017. Results: The most commonly detected groups of banned substances were anabolic agents and stimulants but the distribution of adverse findings per drug class was very different depending on the sports discipline. Weightlifting, athletics, rugby, hockey and volleyball presented abnormally high proportions of anabolic agents (p = 2.8 × 10^-11). Cycling, athletics and rugby presented atypically elevated proportions of peptide hormones and growth factors (p = 1.4 × 10^-1). Diuretics and masking agents were more commonly found in boxing, wrestling, taekwondo, judo, shooting, and gymnastics than in other sports (p = 4.0 × 10^-68). Cycling, rowing, aquatics, tennis, gymnastics and ice hockey presented abnormally high proportions of stimulants (p = 1.8 × 10^-5). Conclusions: These results indicate that the groups of banned substances more commonly detected in anti-doping control tests were different depending on the sports discipline. These data suggest the prohibited substances used as doping agents might be substantially different depending on the type of sport and thus, sports-specific anti-doping policies should be implemented to enhance the efficacy of anti-doping testing.

A Warning against the Negligent Use of Cannabidiol in Professional and Amateur Athletes

Cannabidiol (CBD) is a non-psychoactive cannabinoid, widely marketed to athletes for claimed effects such as decreased anxiety, fear memory extinction, anti-inflammatory properties, relief of pain and for post-exercise recovery. The World Anti-Doping Agency (WADA) has excluded CBD from its list of prohibited substances. Nevertheless, caution is currently advised for athletes intending to use the compound-except CBD, all other cannabinoids are still on the prohibited list. CBD products, specifically non-medicinal, so-called full-spectrum cannabis extracts, may contain significant levels of these substances, but also contaminations of tetrahydrocannabinol (THC) (>2.5 mg/day in >30% of products on the German market) potentially leading to positive doping tests. Labelled claims about CBD content and absence of THC are often false and misleading. Contaminations with the psychoactive THC can result in adverse effects on cognition and, in general, the safety profile of CBD with respect to its toxicity is a controversial topic of discussion. For these reasons, we would currently advise against the use of over-the-counter CBD products, especially those from dubious internet sources without quality control.

Cannabis use and physical activity among 89,777 adolescents aged 12-15 years from 21 low- and middle-income countries

BACKGROUND

Cannabis legalization and use are increasing globally, however, little is known about associations between cannabis use and other health behaviors, such as physical activity (PA). Importantly, the extent to which cannabis use is associated with PA in adolescents is yet to be explored in low- and middle-income countries (LMICs), where there may be unique sociodemographic and environmental characteristics compared with high-income countries. Therefore, this study examined the association between PA and cannabis use among adolescents in 21 LMICs using data from the 2010-2016 Global School-based Student Health Survey.

METHODS

A multivariable logistic regression analysis was performed among a final sample of 89,777 adolescents (49.2% females) aged 12-15 years with a mean (SD) age of 13.7 (0.9) years.

RESULTS

The overall prevalence of past (i.e., in lifetime but not in past 30 days) and current (in past 30 days) cannabis use were 1.0% and 2.9% respectively, while the prevalence of adequate PA in the past week (7 days/week of 60 min of PA) was 16.6%. The prevalence of adequate levels of PA in past and current cannabis use was 7.3% and 6.9%, respectively. Current and past cannabis use (vs. never) were associated with a significant 0.62 (95% CI = 0.41-0.94) and 0.43 (95%CI = 0.30-0.63) times lower odds for achieving adequate levels of PA, respectively.

CONCLUSION

The results underscore the high prevalence of low PA among adolescents in LMICs, and emphasize the need to understand behavioral factors that may affect PA levels, such as cannabis use, when designing interventions to improve health.

Cannabis Associated "High" Cardiovascular Morbidity and Mortality: Marijuana Smoke Like Tobacco Smoke? A Déjà Vu/Déjà Vécu Story?

BACKGROUND

Cannabis use has increased over the past several years as some countries have legalized its use for the treatment of certain medical conditions and/or for recreational use. Thus, concerns have risen about potential adverse health effects. Increasing number of reports have associated cannabis use with serious cardiovascular (CV) complications. Furthermore, there appears to be a likeness in the harmful health effects, especially on the CV and respiratory systems, of cannabis smoking to those of tobacco smoking.

OBJECTIVE

To review the CV effects of cannabis use and compare them with those of tobacco use.

METHODS

Articles were reviewed that were published in English literature reporting on cannabis and cannabinoid pharmacology and their effects on the CV system and their consequences. Emphasis was also placed on articles reporting on cannabis use in adolescents, exposure to secondhand smoke, its effect on exercise and finally its inter-relationship and similarities with tobacco use.

RESULTS

With growing cannabis use, an increasing number of reports have emerged associating marijuana use with serious and life-threatening CV complications, including acute coronary syndromes, potentially lethal cardiac arrhythmias and ischemic strokes. There are certain similarities of the deleterious CV and respiratory effects of cannabis smoking with those of tobacco smoking. Despite the difference in the active ingredients (tetrahydrocannabinol vs. nicotine), each substance produces a plethora of chemicals when smoked and these are largely identical; furthermore, due to different modes of smoking, cannabis chemicals are retained in the body for a longer time. Of course, concomitant tobacco and cannabis smoking is a perplexing factor in isolating damages specifically pertaining to cannabis use, while the health risk is additive. Although the mechanisms producing CV harm may be somewhat different between these two substances, the outcome appears similar, or even worse, as the effects may emerge at a younger age.

CONCLUSION

There is an increasing concern that, apart from the mental health problem with cannabis smoking, societies may be facing another wave of a déjà vu/déjà vécu phenomenon similar to the tobacco smoking story.

Review of WADA Prohibited Substances: Limited Evidence for Performance-Enhancing Effects

The World Anti-Doping Agency is responsible for maintaining a Prohibited List that describes the use of substances and methods that are prohibited for athletes. The list currently contains 23 substance classes, and an important reason for the existence of this list is to prevent unfair competition due to pharmacologically enhanced performance. The aim of this review was to give an overview of the available evidence for performance enhancement of these substance classes. We searched the scientific literature through PubMed for studies and reviews evaluating the effects of substance classes on performance. Findings from double-blind, randomized controlled trials were considered as evidence for (the absence of) effects if they were performed in trained subjects measuring relevant performance outcomes. Only 5 of 23 substance classes show evidence of having the ability to enhance actual sports performance, i.e. anabolic agents, β2-agonists, stimulants, glucocorticoids and β-blockers. One additional class, growth hormone, has similar evidence but only in untrained subjects. The observed effects all relate to strength or sprint performance (and accuracy for β-blockers); there are no studies showing positive effects on reliable markers of endurance performance. For 11 classes, no well-designed studies are available, and, for the remaining six classes, there is evidence of an absence of a positive effect. In conclusion, for the majority of substance classes, no convincing evidence for performance enhancement is available, while, for the remaining classes, the evidence is based on a total of only 266 subjects from 11 studies.

Factors associated with cannabis use change in youth: Evidence from the COMPASS study

INTRODUCTION

Harmful effects of cannabis use in youth scale with frequency. In the context of approaching legalization in Canada, understanding the distinctions between youth who change and who maintain their cannabis use is essential for designing interventions and policy. A substantial number of characteristics may play a role. This study assessed whether and how youth who change their cannabis use differ from those who do not.

METHODS

Cannabis use was reported by 8375 Canadian high school students participating in the COMPASS study. GEE multiple logistic regressions were then used to establish impact of 13 baseline demographic and behavioural exposure variables on the likelihood of membership in four frequency change groups at follow-up a year later: reduction, cessation, escalation, and maintenance.

RESULTS

Groups were found to differ in several ways. Cessation group members (19.4% of users) were less likely to binge drink (OR 0.82), vape (OR 0.82), or attend class without completing homework (OR 0.72) than maintainers. Students who reduced their use (14.6% of users) were more likely to binge drink (OR 1.36), smoke (OR 1.20), and skip class (OR 1.21). Those who escalated (29.5% of users) were more likely to be male (OR 1.35) and to vape (OR 1.22).

CONCLUSIONS

Students who change their cannabis use differ in several demographic and behavioural characteristics. The results raise further concerns about the impact of e-cigarettes and the role of poly-substance use in high-risk trajectories. Distinct classes of cannabis users, essential for policy and intervention development, can be identified in high school populations.

Cannabis and the Health and Performance of the Elite Athlete

OBJECTIVE

Cannabis (marijuana) is undergoing extensive regulatory review in many global jurisdictions for medical and nonmedical access. Cannabis has potential impact on the health of athletes as well as on performance in both training and in competition. The aim of this general review is to identify and highlight the challenges in interpreting information with respect to elite athletic performance, and to point to important research areas that need to be addressed.

DATA SOURCES

A nonsystematic literature review was conducted using Medline and PubMed for articles related to cannabis/marijuana use and sports/athletic performance; abstracts were reviewed by lead author and key themes identified and explored.

MAIN RESULTS

Cannabis may be primarily inhaled or ingested orally for a range of medical and nonmedical reasons; evidence for efficacy is limited but promising for chronic pain management. Although evidence for serious harms from cannabis use on health of athletes is limited, one should be cognizant of the potential for abuse and mental health issues. Although the prevalence of cannabis use among elite athletes is not well-known, use is associated with certain high-risk sports. There is no evidence for cannabis use as a performance-enhancing drug.

CONCLUSIONS

Medical and nonmedical cannabis use among athletes reflects changing societal and cultural norms and experiences. Although cannabis use is more prevalent in some athletes engaged in high-risk sports, there is no direct evidence of performance-enhancing effects in athletes. The potential beneficial effects of cannabis as part of a pain management protocol, including reducing concussion-related symptoms, deserve further attention.

Beyond deficit and harm reduction: Incorporating the spectrum of wellness as an interpretive framework for cannabis consumption

The cannabis academic literature is informed by dominant deficit, public health and harm reduction frameworks. However, a large majority of cannabis consumption appears to place outside the scope of these models that prioritise the identification and limitation of negative impacts. As such there are apparent analytical blind spots pertaining to: non-problematic use of cannabis (as defined by Global Commission on Drug Policy); the intersection of medical and recreational intents of use; and pleasure. This paper explores the academic and grey literature relating to the spectrum of wellness to assess its suitability as a framework for cannabis scholars. For millennia cannabis use has been associated with wellness models, particularly at the nexus of mind, body, and spirit. Despite this seemingly obvious match, the academic literature that incorporates cannabis consumption patterns into wellness conceptions is thin. The spectrum of wellness has both advantages and disadvantages compared to existing models and may be useful as a complementary framework that allows for broader examination of cannabis consumer activity.