When it comes to the brain-benefits of exercise, we might vaguely throw around the terms ‘endorphin rush’ or ‘runner’s high’, but what do they really mean? Adapted from an article by Alice Ball

The so-called runner’s high is real, and even if pounding the pavements isn’t your thing, non-runners can still experience this sense of elation after a workout

Any exercise puts the body under stress and pain; and since the 1970s, it’s been assumed that the body’s response to exercise-induced stress is to trigger the release of endorphins.

Endorphins are neurotransmitters produced by the brain’s hypothalamus and pituitary gland.

They’re structurally similar to the drug morphine and have similar opiate effects in relieving pain and boosting feelings of pleasure and euphoria.

But Dr Michael Mosley, TV presenter and science journalist, told Optimum Nutrition that while studies show endorphin levels in the blood spike after exercise, there is one major “incompletion” in the hypothesis.

Endorphin molecules are too big to cross the blood-brain barrier, meaning it’s unlikely that they have a direct effect on brain function during exercise.

“Instead, there is mounting evidence for the importance of endocannabinoids (eCBs) when it comes to explaining the athlete’s ‘high’,” he said.

“Endocannabinoids are produced throughout the body and have many functions. As well as making you feel good they reduce inflammation and increase insulin sensitivity, affecting fat and energy metabolism.”

Getting high while getting fit

Research has found that after exercise, levels of eCBs are elevated.

One study which monitored male college students running or cycling for 50 minutes found that exercise of moderate-intensity dramatically increased concentrations of anandamide (a type of endocannabinoid) in blood plasma.

Unlike endorphins, these eCBs can travel from the blood into the brain, where it’s believed that they trigger this post-exercise euphoria.

What’s more, eCBs are structurally similar to cannabis, which can explain the pain-relieving and appetite-inducing sensations you might experience after a workout.

However, keep in mind that the mood-boosting effects of exercise aren’t limited to one system. Enter two other neurotransmitters: serotonin and dopamine.

Low-levels of both can lead to low mood and depressive symptoms, but physical activity can reverse this, boosting mood and sense of wellbeing.

Increase endorphins by working out together

How can we achieve this euphoric state? One answer could be through group training.

A study from the University of Oxford found that rowers who exercised together experienced a significant increase in endorphin release compared with solo rowers, while the athlete’s pain thresholds also increased when training as a group.

The researchers went on to suggest that this heightened effect from synchronised physical activity may explain the sense of euphoria experienced during other social activities, like laughing or dancing.

Hannah Tyldesley and Emily Kier, known on social media as the running duo Twice the Health, are firm believers that training together promotes their athletes’ highs.

They told us: “One of the many reasons we started up our run and cycle clubs was because we believe that exercising with others is more enjoyable.

“There has been no better feeling than reaching the top of the South Rim of the Grand Canyon together after a 50 km run through it.

“It’s truly special to share a run like that with someone else, especially your best bud.”

Danny Bent, founder of London-based fitness programme Project Awesome, agrees.

Project Awesome offers “free, fun, loud and colourful” running classes to people of all abilities, with those taking part encouraged to don bright colours, ‘80’s-style leg-warmers and stop for “20-second dance interludes” mid-run.

“People are clearly buzzing after the workouts,” says Bent, who believes the sense of community and post-workout coffee sessions keep them coming back.

“They say they’re 10 times more productive at work on a Project Awesome day.”

This buzz could also be down to the outdoor nature of Project Awesome, as research suggests that exercising outdoors can leave people feeling more energetic and positive compared to training indoors.

Change up the intensity

But what happens if your workout partner bails or the great British weather takes a drizzly turn?

Well, good news: you can still achieve an athlete’s high by alternating the intensity of your training.

Research from the University of Arizona, USA, suggests that moderate-intensity exercise (70-85 per cent of your maximum heart rate) is best for triggering a high.

This is because it creates an environment in which blood flow is maximised and endocannabinoid receptors are the most stimulated and receptive.

Research from the University of Turku, Finland, does suggest differently.

Researchers compared opioid release after moderate- and high-intensity exercise, finding that high-intensity interval training (HIIT) led to the biggest increase in endorphin flow.

But don’t sweat it; moderate-intensity aerobic workouts still left participants feeling euphoric, suggesting that the athlete’s high really is a subjective experience

 There could be more ways to increase that workout buzz too.

A study from McGill University, Canada, found that dopamine levels increased by nine per cent when participants listened to their favourite music.

So if you’re working out alone, consider wearing headphones to increase euphoria.

Meanwhile, Stuart Walton, fitness coach and co-founder of fitness plan MyActiveSelf, believes in working towards a personal goal.

“Whilst research shows a buzz or high as a result of exercise, the same can be said for achieving a goal and the milestones along the way,” he says.

“It’s the consistency over a period of time that will lead to the achievement of these long-term goals and the highs that go with them.”

However, according to Walton, the most important factor is finding an activity that you enjoy.

“I ask people to consider if they aren’t feeling a high from the exercise or sport they choose to do, why are they doing it in the first place?” he says.

The solution? “Switch — it really is that easy.”

The psychological factor

Of course, there’s the possibility that the athlete’s high could all be in our heads.

Journalist Kate Ng Shu-Yi says: “After an intense HIIT workout I feel pumped — I can feel the blood pounding in my ears and I don’t feel the pain as much.

“But it’s the realisation of ‘I actually did that’ that makes me feel this way, like I’ve really impressed myself.”

Scotty McGlynn, activist and podcast host, adds: “I swim five days a week for one hour, it gives me a feeling that I just can’t live without now.”

Whether you need to dig out your retro leg-warmers, throw on a banging playlist or grab a friend, there are endless ways to feel a buzz from your workout.

And who knows, if you work hard enough you could be on your way to basking in the glory of your newfound athlete’s high.

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