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Is cannabis performance enhancing?

The University of Colorado announces groundbreaking research on the correlation between cannabis and exercise

US sprinter Sha’Carri Richardson broke the internet last summer when she was suspended for testing positive for cannabis use after her 100m win at U.S. Olympic Trials. USATF and World Athletics received some backlash as there is little scientific research on whether cannabidiol (CBD) and tetrahydrocannabinol (THC) hinder or help athletic performance. A new study out of the University of Colorado Boulder hopes to shed some light on how cannabis, which is now legal outside of sport, impacts exercise.

Sha’Carri Richardson before her 100m at the Eugene Diamond League. Photo: Jonathan Ferrey / Getty Images

Under World Athletics and World Anti-Doping Agency rules, cannabis is a banned substance that meets two of the following three criteria:

  1. It has the potential to enhance sport performance
  2. The substance represents an actual or potential health risk to the athlete
  3. Use of the substance violates the spirit of the sport 

In ultrarunning, cannabis has been seen to have benefits such as numbing pain, minimizing nausea and alleviating fatigue. Ultimately, cannabis is seen as a performance-enhancing substance and is illegal at all levels of competition.

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“Cannabis is often associated with a decrease in motivation. But we are seeing an increasing number of unscientific reports of athletes using it while playing golf or practicing yoga, to snowboarding and running,” said Laurel Gibson, a PhD neuroscience student, who is conducting the study.

The observations involved three 15-minute sessions. First, subjects were required to take a baseline cognitive and physical test, then assigned to use either a CBD or THC-dominant strain of cannabis while running; after there was a follow-up where they work out sober. After the two tests, they were asked a few questions about their workout experience.

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Heather Mashhoodi, an ultrarunner currently training 80 to 100 miles per week, participated in the study. She immediately noticed that using cannabis did not help her performance, but found it psychologically enhancing. “When I used cannabis it made colours brighter and my thoughts clearer,” Mashoodi said. “I felt more emotionally in tune.” 

The researchers had Mashhoodi run several 15 minute time trials on a treadmill while monitoring her physical exertion and performance with and without cannabis in her system. Although she performed better without the substance, she said she felt more relaxed while taking cannabis.




The goal of the study was to see how cannabis influences pain, motivation and physical exertion. In a previous survey of cannabis users, they found that 80 per cent of users take the substance during their workout, while 70 per cent said that it increases the enjoyment of the workout. Only 52 per cent said that cannabis helped them with motivation.

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In past research, cannabis has been shown to have anti-inflammatory and painkilling effects on the body. “If cannabis eases pain and inflammation, it could be revolutionary in helping older adults exercise,” said Angela Bryan, a professor of neuroscience at CU Boulder.

Ultimately, the researchers hope their findings can help engage discussion at doctors’ offices and governing bodies of sport, which will soon be re-evaluating whether cannabis should remain on the banned substance list. The study was conducted to give policymakers and health care practitioners in the industry more information to make an educated decision on cannabis use.