Understanding The Cannabis-Body Connection With Exercise

17:33 minutes

Hemp plant held up by researcher.
Researcher holding a hemp plant. Credit: Shutterstock

As a person gets ready for a long run, there are a few things they need: keys, cellphone, earbuds. But what about a weed gummy? It may not fit the stereotype of the stoner locked on the couch eating chips. But as cannabis is legalized in an increasing number of states, anecdotal evidence points to a growing community of people mixing cannabis with exercise. In fact, a 2019 study from the University of Colorado Boulder found 80% of users in states where marijuana is legal use it as part of their workout routine. 

Prior research suggests there’s a good reason for this, especially for endurance athletes: the notorious feeling of “runner’s high,” which has been described as euphoria and tied to pain relief, appears to be connected to the body’s endocannabinoid system

Despite its different legal status in various states, marijuana is still classified federally as a Schedule I drug, putting it in the same category as heroin and meth. That affects the research able to be done with cannabis.

Guest host Miles O’Brien talks to two people involved in the first human study of how cannabis and exercise interact: Laurel Gibson, PhD candidate in psychology and neuroscience at the University of Colorado Boulder, and ultramarathoner and study participant Heather Mashhoodi, also based in Boulder.

Further Reading

Donate To Science Friday

Invest in quality science journalism by making a donation to Science Friday.


Segment Guests

Laurel Gibson

Laurel Gibson is a PhD candidate in psychology and neuroscience at the University of Colorado Boulder. 

Heather Mashhoodi

Heather Mashhoodi is an ultramarathoner based in Boulder. 

Segment Transcript

MILES O’BRIEN: Imagine you’re getting ready for a long run. What are the things you need? You make sure your sneakers are tied, double knots preferred, some headphones for you to listen to music or the Science Friday podcast, and maybe, just maybe, a cannabis gummy or a puff on a joint.

This doesn’t quite fit the stereotype of the stoner locked on the couch munching a bowl of chips. But as cannabis is legalized in an increasing number of states, we’re learning anecdotally about all the ways people use weed in their lives. For a growing community of people, that means mixing cannabis with exercise.

But federally, cannabis is still classified as a Schedule I drug, and that means it’s in the same legal category as heroin and meth. And that means it’s really hard for researchers to do studies on how cannabis impacts people. In Colorado, one of the first studies in humans on how cannabis and exercise mix is underway.

And joining me today are two people involved. Laurel Gibson is a PhD candidate in psychology and neuroscience at the University of Colorado in Boulder. Heather Mashudi is an ultra-marathoner and research participant, also joining us from Boulder. Welcome to both of you to Science Friday.

LAUREL GIBSON: Thanks for having us.

HEATHER MASHUDI: Thanks for having us.

MILES O’BRIEN: So Laurel, walk me through this. This is, I guess, the ultimate runner’s high. Had to get that one out there. What are the goals of your study?

LAUREL GIBSON: Sure, so for this study we’re really interested in how cannabis influences the experience of exercise. So more for the subjective experience versus exercise performance, per se. So we’re really curious about how cannabis might either remove or add barriers associated with regular exercise. So we’re looking at things like pain, motivation, enjoyment, dissociation, things like that. So we’re really curious to see how acute cannabis use of varying cannabinoid profiles– so THC and CBD– how that might help or hinder people who are interested in exercising more.

MILES O’BRIEN: So Heather, you’re an ultra-marathoner, which means you log some serious mileage. I’d like to hear a little bit about that. But how does cannabis fit into your regime?

HEATHER MASHUDI: Yeah. I do log some serious mileage in my peak training weeks. I try to hit 100-mile weeks. And I think once a week, I have a long run, and usually that’s about half of the distance of whatever race I’m doing. So for a hundred-mile race, I want to try and hit a 50-mile long run.

And on my long runs, it’s usually on a weekend. It’s kind of a treat day. And so my protocol for that is to try and get halfway through my long run and then eat about a 5-milligram gummy. I don’t have a good enough tolerance for any more than 5. And yeah, I usually get those effects of kind of a blissful, connected state with nature, which is what I’m out there for originally, so it’s good to kind of enhance that effect.

MILES O’BRIEN: All right. So help us understand a little bit of what you’re finding. We know about runner’s high. And we’ve always said, oh, endorphins. But maybe it’s not. Is it something to do, perhaps, with the endocannabinoid system? Is that what you’re finding?

LAUREL GIBSON: So I can’t speak necessarily to this study in particular, because we haven’t analyzed any of our data yet. We’re waiting until we’re done collecting participants. But what we do know from other researchers is it seems like the endocannabinoid system is playing a role in this runner’s high, which is what long-distance runners often experience, such as euphoria, feelings of effortlessness, things like that.

And so what scientists are beginning to think is that it’s actually endocannabinoids and not endorphins causing this, because endocannabinoids are able to cross the blood-brain barrier. And what studies have shown is that acute exercise actually increases circulating endocannabinoids, and this release is associated with reductions in pain, reductions in exertion, and things like that. So it’s still to be determined whether exogenous cannabinoids like THC or CBD might kind of mimic this process, or if they might interfere with it in some way. So we’re curious to see what we find.

MILES O’BRIEN: My guests are Laurel Gibson, PhD candidate in psychology and neuroscience at the University of Colorado in Boulder, and Heather Mashudi, ultra-marathoner and research participant, also joining us from Boulder. You know, it’s interesting. I think timing and dosage are so important. And I do know, when you ingest with a gummy, it takes a little while for the effects to take hold. How do you time it?

HEATHER MASHUDI: So timing is relative to miles I’m already in. So halfway through a long run– right now I’m running 20-mile long runs, so it would be 10 miles in I would take it. And the reason why is because usually, halfway through, that’s when the pain really starts to kick in. And also, that’s when the kind of natural endocannabinoid system is working and I’m starting to feel connected and just kind of in a trance and flow state. And so that’s when I try to time taking the gummy.

MILES O’BRIEN: You’re kind of getting your runner’s high mid-run. You’re sort of changing the time frame when you experience that feeling. And I assume, if nothing else, it makes your run more pleasant. But do you think it changes the way you run?

HEATHER MASHUDI: I think if anything, the biggest benefit is the psychological aspect, even more than pain relief. So you know, I think maybe what we haven’t touched on yet is just, this class of drugs more so enhancing our feelings of connectedness. And I know this sounds kind of, like, ethereal and hippy dippy, but it’s really– it was a motivator for me to originally even start long-distance running, was, the trees are so much greener and, you know, oh, the dirt is at the perfect humidity. I mean, weird stuff happens. But it’s really quite transformational.

MILES O’BRIEN: You say you use the gummy in the middle of one of your very long runs. Would you be reluctant to smoke it? Because you are, after all, a long-distance marathoner and probably are concerned about your lung capacity.

HEATHER MASHUDI: Yeah, and to participate in Laurel’s study I did use flower, but it’s definitely not incorporated into my regular routine when I run. And I’m in Colorado doing a lot of higher elevation stuff. But I know athletes who run and use flower, so it’s not far, far off.

MILES O’BRIEN: Laurel, let’s talk a little bit more about how you’ve created this study. How is it set up? Is the way Heather described it kind of typical? I mean, not everybody’s running those long distances. So how do you try to understand how this works beyond anecdotal information?

LAUREL GIBSON: Yeah, that’s a great question. And it’s true that people are really running a variety of different mileages when they’re doing this on their own. And unfortunately, we don’t have the time for folks to come into the lab and get out a 50-mile long run, right?

So for this study, we standardized it across participants, and we have folks run in 30-minute sessions. And so participants come into our lab three different times. The first is just for a baseline, where we get some measurements of BMI. We do an exercise test to determine the speed and the intensity that they need to be at when engaging in moderate intensity exercise. And then we also have them fill out a survey.

And then folks come in an additional two times. One time, they will use their assigned cannabis product beforehand, come into the lab, do a 30-minute run while they’re high, and fill out some measures during that time. And then the other time, they come in when they’re sober. So that’s our non-cannabis exercise session. And they run again for 30 minutes.

MILES O’BRIEN: So let’s talk about, Laurel, the limitations on research. It wasn’t too long ago that if you were doing research at a university involving cannabis, there was, like, one place in the country, in Mississippi, to go get the bud. And it really wasn’t analogous to what a typical person could get in a dispensary. So it was kind of– didn’t have a lot of usefulness for scientists. How have you kind of gotten around that, because you don’t want to end up on the wrong side of the DEA, do you?

LAUREL GIBSON: Yeah, it’s tough. And I will say that research is still going on with NIDA-grown cannabis. And if you want to have folks actually use cannabis on a university campus in a lab setting, that’s the stuff you need to use. But you’re right. It doesn’t necessarily reflect what people are actually using when they go to a dispensary in a legal market and get their products.

So we kind of have to jump through some loopholes in our lab to study legal-market cannabis. And one of those loopholes is we can’t actually have participants use in our lab, because CU is a federal institution and cannabis is still illegal at the federal level, right? So what we do instead to get around this is we have our mobile pharmacology lab, which some of our participants like to call the Cannavan, and we will drive that mobile lab to participants’ homes.

Participants use their product in their own homes. Up to them how much they want to use. And then they come back out to the mobile lab. And typically, for our other cannabis studies, you would just stay in the mobile lab. You would do all the assessments, all the measures, in there.

But for this study, we unfortunately can’t fit a treadmill in the mobile lab, even though we talked about it. So what we do instead is we have people driven back to campus while they’re still high. And then once they get to our exercise facility, they’ll run on our treadmills.

MILES O’BRIEN: So there’s a van that comes by. It’s like the Good Humor truck for adults, I guess, or something like that.


MILES O’BRIEN: Good humor indeed. This all seems kind of silly, frankly. Are things changing for the better on this front?

LAUREL GIBSON: Not imminently, no. I think until cannabis is legalized at the federal level, we probably won’t see much of a change in how we conduct studies using legal-market products that are readily available to our participants. And even to a certain extent in Canada, where they recently legalized it at the countrywide level, they’re still facing a lot of barriers to studying these substances in the lab. And so a lot of researchers are still turning to this more observational methodology rather than having participants come into the lab and smoke.

MILES O’BRIEN: Well, how much does that undermine your scientific goals?

LAUREL GIBSON: It’s definitely a limitation. And it’s something that we thought about a lot, right? So we do have various ways of trying to minimize the limitations, I guess you could say.

So one is we want people to still be acutely intoxicated by the time they get to the lab, right? So we keep it within a certain radius of campus. So participants need to live 20 minutes or less from campus so by the time they get there, they’re still high. But it’s kind of, we have to weigh the limitations and strengths of the approach, because we want to study what participants can actually get in a dispensary– the cannabinoid profile, the strength of the product– and that just isn’t always reflected in products that you can get from the government.

MILES O’BRIEN: All right. Well, of course, we know, and we’ve learned this recently, that in athletic endeavors like the Olympics, cannabis is a big no-no. We saw the sprinter Sha’Carri Richardson unable to participate in the summer games because she tested positive for THC. Laurel, does this research in any way lead you to believe it is performance enhancing?

LAUREL GIBSON: So I can’t speak necessarily to the findings from our study yet. But what I will say from what we know from previous studies that have looked at cannabis and exercise performance, from the standpoint of performance enhancing in terms of strength or speed, probably not. But it’s also important to note that the World Anti-Doping Agency isn’t just banning substances based on how they affect sports performance. So it’s also whether they pose a risk to their athletes or whether it influences the spirit of sport, per se. So there are a lot of other factors that go into that decision-making process.

MILES O’BRIEN: So Heather, does it improve your performance?

HEATHER MASHUDI: OK, so I think that we have to define that term. I’m going to speak around it as well as Laurel did.

MILES O’BRIEN: This is a gray area, isn’t it, right? Because if you feel better psychologically, if you recover faster, in a sense, you are enhancing your performance, even though maybe your time– it really gets complicated quickly, doesn’t it?

HEATHER MASHUDI: Yeah, and I think that’s part of my protocol that I bake into my long runs, is I don’t take the gummy until I’m halfway through because I want to get to that point where I’ve earned it. I’ve put in some work to get there. If I do it before halfway, I’m kind of prone sometimes to turn around and be like, yeah, that’s enough. And it’s not that it makes me lazy or unmotivated. It’s just, like, I’m more in tune with my body and my feelings, and I’m less likely to push myself. So I guess that’s a more concrete anecdotal answer, probably, for you.

MILES O’BRIEN: Should it be allowed in competitions like the Olympics?

HEATHER MASHUDI: I’m not going to give you a yes or no. I wouldn’t do it on a race day, right? And for me, it’s just to make the training more enjoyable, to make those long slogs kind of a treat, something that I look forward to during the week.

MILES O’BRIEN: And you wouldn’t do it in a competition because why?

HEATHER MASHUDI: I just think for me, I’m kind of a square, too, right, in that like– a lot of runners will take a whole bunch of caffeine pills with them. I’m kind of like, let’s just see how far I can take this myself, on my own energy metabolism system. I think that’s a personal thing.

MILES O’BRIEN: That’s really interesting. You kind of get in the zone, in that flow, and this assists. Now, you do have a background in the sciences, neuroscience in particular. Is that what led you to this study?

HEATHER MASHUDI: Yeah, I guess I’m a citizen scientist. I’m an ally. I’m by no means a scientist. So I definitely have a strong passion for being a research participant.

I am, like, totally enamored with Laurel’s work in her lab and her motivation to do this as her dissertation. It’s a really large sample size she’s trying to get to, and it’s a really, really cool idea, especially being in Boulder. So you know, I’m just– I’m really passionate about the ways that we can help as allies, help scientists and researchers, especially with harder stuff, Schedule I stuff, right?

MILES O’BRIEN: Well, walk us through. There’s any number of ways to ingest cannabis. You can Inhale it, you can vape it, you can smoke it. What are the pros and cons?

LAUREL GIBSON: Sure, so what we have seen anecdotally, especially among ultra-runners and folks running longer distances, is it’s more common to use edibles because they metabolize a bit slower and their effects are longer lasting. But we’ve also seen at the same time that people who run shorter distance are more likely to turn to cannabis flower, because its acute effects happen faster. And so for our study, we’re looking at the effects of cannabis flower rather than edibles, just because cannabis edibles metabolize so much differently from participant to participant, and there isn’t really a standardized length of time to wait.

So we have all our participants use cannabis flower. Up to them how they want to use it, if they want to use a vaporizer, a joint, or a bowl. But that’s what they smoke before coming into the lab.

MILES O’BRIEN: I’m curious about what strains of marijuana you’re using. Do you use an indica, a sativa, or some kind of hybrid?

LAUREL GIBSON: So that’s a good question. And actually, in terms of the scientific evidence out there, there’s not much distinguishing the effects of indica, sativa, and hybrids. That’s more of an anecdotal report. So what we’re focusing on instead is various ratios of cannabinoids. So we’re using two different strains. One is a THC-heavy strain, and then one is a CBD-heavy strain, for our study.

MILES O’BRIEN: That’s interesting, because when you go to a dispensary, they’ll tell you sativa is more for focus and being awake, and–


MILES O’BRIEN: –the indica is more for lying on the couch. And that’s not true?

LAUREL GIBSON: I won’t say that it’s not true. There’s just not much scientific evidence out there saying that there are different effects. So we’re choosing to just focus on THC versus CBD. And I would love to see a study out there eventually that looks at whether indica and sativa really does have different effects, or if that’s something that you see more in dispensaries and in pop culture.

MILES O’BRIEN: That’s all the time we have. Thank you to my guests. Laurel Gibson is a PhD candidate in psychology and neuroscience at the University of Colorado in Boulder. And Heather Mashudi is an ultra-marathoner and research participant, also joining us from Boulder.

HEATHER MASHUDI: Thanks for having us. Long-time listener.

LAUREL GIBSON: Thank you for having us.

Copyright © 2022 Science Friday Initiative. All rights reserved. Science Friday transcripts are produced on a tight deadline by 3Play Media. Fidelity to the original aired/published audio or video file might vary, and text might be updated or amended in the future. For the authoritative record of Science Friday’s programming, please visit the original aired/published recording. For terms of use and more information, visit our policies pages at http://www.sciencefriday.com/about/policies/

Meet the Producers and Host

About Kathleen Davis

Kathleen Davis is a producer at Science Friday, which means she spends the week brainstorming, researching, and writing, typically in that order. She’s a big fan of stories related to strange animal facts and dystopian technology.

About Miles O’Brien

Miles O’Brien is a science correspondent for PBS NewsHour, a producer and director for the PBS science documentary series NOVA, and a correspondent for the PBS documentary series FRONTLINE and the National Science Foundation Science Nation series.

Explore More