This article was originally published April 20, 2017.

Some people stretch before they workout. Others smoke a joint.

With marijuana legalization on Canada's horizon, and legislation already passed in some parts of the United States, it's no surprise weed is being embraced in new circles – including athletics. And it's not just stereotypical stoner snowboarders getting high. Athletes from long-distance runners to weight lifters are mixing pot into their pre-workout routine, and Ontarians can even expect the 420 Games – a series of athletic events for pot-enthusiasts held across the U.S. – to come to the province this fall.

But while some athletes are raving about it, the science is out on whether toking up actually benefits your workout.

"People who do really long running, like triathletes and people who do 100-mile (races), talk about getting into a flow state (after consuming cannabis)," said Keith Humphreys, a professor of psychiatry at Stanford University's school of medicine.

"At the same time, depending on what you use, you could do worse on your time, you could get more easily distracted, your form could degrade."

Humphreys said cannabis consumption affects different people differently. It could potentially improve one person's athletic performance by decreasing anxiety, and hamper another person's by triggering a panic attack, he said.

So what's actually happening to your body when you consume cannabis?

Humphreys explained that cannabinoids THC and CBD — the active compounds found in cannabis — bind to receptors in your body, in turn changing internal signalling systems. For instance, you might experience increased desire to eat, an absence of pain, or decreased anxiety, none of which you'd experience to that level without cannabis.

These effects could potentially help athletes who need to remain calm in sports such as archery, or those who want to feel no pain while working out, he said. But these are impairments, and can be a double-edged sword, said Humphreys. Some seem pretty obvious! "You feel pretty relaxed doing that downhill course you've never tried before," he said. "But you should feel anxious because you're not good enough to do it and you're going to have an accident."

CBD in cannabis is also thought to have anti-inflammatory properties, he said. This means if taken after a workout, you might experience less inflammation, and less pain.

But the science is still out on just how beneficial, or detrimental, weed is to your workout.

"It's stupidly hard to study cannabinoids," said Humphreys, noting restrictions U.S. scientists face in trying to study marijuana. "There's nowhere near enough research and a lot of it isn't very good."

In the meantime, elite athletes like Clifford Drusinsky, a U.S. triathlete who consumes THC-infused energy bars before training, have long sang the praises of marijuana. "Marijuana relaxes me and allows me to go into a controlled, meditational place," Drusinsky told Men's Journal in 2014. "When I get high, I train smarter and focus on form."

Indeed, there are even pro-pot gyms popping up in San Fransisco and Denver, where recreational marijuana use is legal. And in Canada, Jim McAlpine, founder of the 420 Games, confirmed to CBC Life he plans to bring the games to Ontario, possibly Hamilton, this October.

But while the buzz around weed and workouts is getting more intense, Toronto-based personal trainer Sergio Pedemonte said he only knows of athletes who use cannabis after working out.

"It's like an Advil. It just relaxes the muscles," said Pedemonte, who co-owns Your House Fitness and works with MMA fighters. "I've heard really good things about it from people who put their bodies under that kind of stress." But a mid-workout toke? He advises against it.

"During a workout, I would never recommend it," Pedemonte said. "I would recommend just a really good warm-up."

Katrina Clarke is a Vancouver- and Toronto-based journalist who writes about relationships, health, technology and social trends. You can find her on Twitter at @KatrinaAClarke.