On a morning run yesterday – about 5 miles in – the thought came upon me that I am happiest when my body is in motion. I was alone, running slowly along country lanes and forest tracks, letting my mind flit between big questions and trivialities, between my inner landscape and the outer one. I felt entirely content in my own, slightly sweaty, skin.
I am not the only one who finds peace of mind in movement. In a 2018 survey of more than 8,000 runners, [conducted by Glasgow Caledonia University and Strava], 89 per cent of respondents said running made them feel happier. And science supports the link: in a recent University of Edinburgh review, 46 studies drew a positive association between long-term running and positive mental health, while a further 22 showed that even a single run could lift mood and alleviate depression and anxiety.
But how does running work its magic on our minds?
Ask this question and it won’t be long before someone mentions endorphins (the body’s natural painkillers, long purported to be responsible for the famed runner’s high). But the real story is both deeper (a whole host of chemicals affecting mental health are released when we work out) and wider (many of the benefits to our mental wellbeing that we gain through running are nothing to do with brain chemistry).
In an influential paper published in 2016, Professor David Lubans, co-director of the Centre for Active Living and Learning at the University of Newcastle in New South Wales, Australia, suggested three broad mechanisms through which exercise can exert positive effects on mental health: neurobiological, which concerns changes in brain activity and structure; psychosocial, which refers to how physical activity can provide an opportunity for positive experiences like social connection, mastery and exposure to nature; and behavioural: the wider impact of exercise on your lifestyle (for example, instilling a daily routine, promoting healthier eating or improving sleep quality).
“These mechanisms overlap and can work simultaneously,” Lubans tells me. A study published last year offers the perfect example: researchers found that when people first returned to sport and exercise following the Covid lockdowns, the subsequent benefits to mental health and quality of life were less down to their increased physical activity level than to other aspects of participation, including social connection and psychological factors.
Your brain on running
Let’s take this concept of overlapping mechanisms for a run. Even getting out the front door entails overcoming the temptation to remain on the sofa, which gives your self-efficacy (a psychosocial mechanism) a boost. As you get moving, your body and brain respond to the physical demand of exercise by releasing a whole host of different hormones and neurotransmitters (including, but not limited to, those famous endorphins and representing a neurobiological response). For example, levels of serotonin – a neurotransmitter associated with mood regulation and emotional processing – are on the up, as are dopamine, a key part of the brain’s ‘reward’ system, and cortisol, the ‘stress’ hormone.
Hang on; that latter one doesn’t sound good… Well, first of all, cortisol isn’t all bad – it’s an integral part of how the body responds to stress of any kind – physical, psychological – triggering the release of glucose into the bloodstream to provide energy to the muscles and brain. What’s more, exercise tempers the stress response. “Even just a single workout can buffer the effects of subsequent stress,” says Lubans. A study at the University of Westminster in 2018 found that people who exercised prior to a stress-inducing task (these usually involve public speaking or solving problems against the clock) released less cortisol compared to those who rested. There was also an association between subjects’ fitness levels and the amount of cortisol they released. “The fitter you are, the better you get at weathering stresses of all kinds – and the more quickly you recover after stressful situations,” says Lubans.
Back to the run: once you’ve settled into your stride, you might notice that you’re feeling calm and content – this ‘don’t worry be happy’ feeling is largely attributed to a family of neurotransmitters known as endocannabinoids (eCBs). We’ll return to these a little later.
Yesterday’s run took me mostly through green and pleasant surroundings. This too, has been shown to enhance the mental health benefits of running. In one study, mood, self-esteem and nature connectedness all increased after 15 minutes of running in green surroundings (regardless of whether people ran solo or with others) while in another, even just looking at images of nature on a screen while running on a treadmill increased exercise time by 12.7 per cent. “The effect was like a Duracell battery!” says study author Dr Mike Rogerson.
Super nature
Rogerson is part of the Green Exercise Research Team at the University of Essex, which explores how natural environments influence the health and wellbeing benefits of exercise. He has identified two intertwining pathways: “The first is that spending time in green and blue (water) spaces – even when you are just sitting down – is good for you,” says Rogerson. Being in nature is associated with more positive emotions, greater decreases in anxiety and rumination, recovery from mental fatigue, improved mood and a reduction in levels of cortisol compared to urban settings. This is thought to be, at least in part, because we evolved to survive and thrive in natural environments – they are where we feel at home – making them a refuge from the stresses of modern urban life and a great place for mental restoration.
This is something to which Martin Elcoate, a birder and runner from Devon, can attest. “Being outside, focusing on something other than day-to-day matters, is important to me in terms of my mental health,” he says.
Elcoate has always felt a strong connection to nature. “My dad introduced me to birdwatching and natural history at an early age, teaching me to find and identify wildlife,” he says. “One of my earliest memories is of a visit to a local wood to listen to the dawn chorus. The sound of woodpeckers drumming out their beats high above us stays with me.”
Running is a more recently acquired hobby: “I picked it up in my 50s to improve my fitness, but now I run for adventure and exploration. It has given me a different way of engaging with the environment. I notice insects out the corner of my eye, hear bird calls and songs and spot interesting plants in the verges as I run. I tune into what’s around me.”
The effects of spending time in nature aren’t only psychological. The atmosphere in certain natural environments contains health-boosting molecules; phytoncides, in forest air, and negative air ions, close to waterfalls, which are both associated with enhanced immune function and stress reduction.
“Exercise is a vehicle to accessing all of these benefits, alongside its own physical, psychological and social value,” says Rogerson.
His second pathway relates to how the environment (both natural and societal) shapes our behaviour, which in turn, affects our health and wellbeing. For example, there’s some evidence to suggest that people work harder when they exercise outdoors, compared to indoors, while perceiving their effort to be equal in both scenarios. That’s a physical benefit. Rogerson offers a psychological one: “When you run outside, you have to make decisions about which way to go, both on a macro level (route choice) and micro level (shall I run through the puddle or around it?) which gives a greater sense of autonomy than the confines of a treadmill.”
Both pathways are important in their own right says Rogerson, but, like Luban’s overlapping mechanisms, they intertwine and impact upon each other. Another of the Green Exercise Research Team’s studies demonstrates this. Pairs of subjects rode on exercise bikes placed side by side for 15 minutes – once in a laboratory and once outdoors, in open green space. Attention restoration (think recovery from mental fatigue) was greater outdoors, suggesting a bigger boost to wellbeing.
But that wasn’t all. “In the parkland environment, people talked to each other 48 per cent more,” says Rogerson. “It was the same people, the same exercise duration and intensity (the bikes automatically adjusted resistance to maintain a constant power output) – the only thing that differed was the setting.” This increased social interaction, prompted by being outdoors, had a further effect: it raised people’s intention to exercise again. “So now we’re saying the environment can shape not just your exercise experience, but your future behaviour,” explains Rogerson.
That run you went on, a few paragraphs back? It’s now over. You get home, pleasantly fatigued, basking in a glow of accomplishment. You’ve achieved something challenging – go you! This ‘mastery’, as psychologists call it, enhances self-efficacy and perceived competence – you believe in yourself a little bit more. Add to that the fact that you’ve spent an hour or more focusing on running, instead of the ever-spinning carousel of thoughts and worries, and you’ve likely regained some mental energy. All in all, you are probably feeling pretty chipper, meaning you are more likely to do other things that benefit your mental health, such as socialising or practising self-care (ticking the box of Luban’s final mechanism – behavioural change).
What all this tells us is that the effect of physical activity on mental health goes far beyond a chemical buzz – it is both multifaceted and contextual. And, says, Lubans: “It is influenced by where and how we do it and who we do it with. Just strapping someone to a treadmill in a dark room is not going to have the same effect as going for a run outside, with friends.”
Better together
Jon Jaros, a runner from Lydd in Kent, knows this only too well. On a Tuesday in September 2022, Jon lost his wonderful wife Jeni to pancreatic cancer. The following evening, he put on his running shoes and came to our local club’s training session, as he had done for the past five years. “When you’ve been with someone for 50 years, you wonder how you will cope with the grief of losing them,” he tells me, two years on. “I realised straight away I had to carry on running. I’m always in a better place when I’m running.”
I remember, a few weeks after Jeni’s death, asking Jon how he was getting on. We were just back from a group run – drinking tea outside the clubhouse.
“I’m doing all right, thanks,” he replied. “This helps…”
“The running, you mean?”
“Not just the running; the people, the being out in nature – even the tea and cake afterwards.”
Jon is a lifelong runner and had always found pleasure in the act of running. But when he retired seven years ago, he found his social network shrinking, and decided it was time to join a running group. “It was the best thing I ever did,” he says now.
“Social connection is one of the most powerful psychosocial mechanisms behind exercise and mental health,” agrees Lubans. “Of course, there is a preference aspect – some people prefer to exercise alone, and doing so can offer a sense of distraction, a chance to reset. But we humans are social beings, and physical activity provides an opportunity to connect with each other.”
Being with others became especially important for Jon when he was dealing with the immediate aftermath of bereavement. “Support from my running community was absolutely brilliant,” he says. “It really helped me through those first few weeks, giving me a purpose and a focus. If I didn’t turn up, I’d get messages from people asking where I was and if I was OK.”
For Jon, the community afforded by running extended beyond it. “Through the running club I found common interests with others,” he explains. “I’m in an art group and a cycling group and I’ve been to concerts and even on holiday with people I met through the running community. A few weeks after Jeni died, some neighbours came to see how I was doing. They said they’d tried coming to see me a few times, but I was never in!”
Jon recently trained to be a running leader, enabling him to be part of the team delivering our running club’s sessions. This desire to ‘give back’ to the running community, alongside achieving something for oneself, was also found to be a major motivator in what gets thousands of people up every Saturday morning, according to a study on Parkrun. While the lure of better health and fitness was what drove people to take part in the weekly global 5km event in the first place, once they’d become Parkrunners, they valued its inclusivity and sense of community, and the opportunity to help others.
Collective joy
The terms ‘collective effervescence’ and ‘collective joy’ have been used to describe the sense of wellbeing, connection and belonging that can come from exercising in the company of others.
You’re most likely to feel collective joy when moving in sync – be that a Zumba class or a club run. I experienced it myself, recently. There were a group of us, running close together during a tempo effort, and gradually we fell into step, our feet striking the ground at the same cadence, our inhales and exhales matching. It felt incredible: as if the energy and the effort of the group was carrying me along. Afterwards, we found we’d all experienced the same thing.
Some research has found that moving in unison, so-called ‘motor synchronisation’, can influence psychological responses too, such as cooperativeness, pro-social behaviour (like helping each other and sharing) and bonding – and the more you get your heart rate up, the closer you feel to those you are moving with.
“Our capacity for collective effervescence is rooted in our need to cooperate to survive,” says Kelly McGonigal, a health psychologist at Stanford University who specialises in understanding the mind-body connection. That, perhaps, is why our brains reward us for it: studies show that moving in synchronicity activates the endogenous opioid system – hello again, endorphins! – associated with increased pain tolerance and feelings of pleasure.
McGonigal draws a parallel between this and the evolutionary biology theory behind the runner’s high. “The neurochemical state that makes running gratifying may have originally served as a reward to keep early humans hunting and gathering,” she explains.
As we now know, a whole host of chemical messengers within the body and brain are activated by running – from oxytocin, more commonly associated with maternal and couple bonding, to cortisol, dopamine to endorphins, and even brain-derived neurotrophic factor (BDNF), associated with the growth of new neurons, particularly in the hippocampus. But when it comes to the runner’s high, endocannabinoids are now believed to play the biggest role. In a 2023 review, 14 out of 17 studies reported a rise in eCBs following sustained exercise of moderate intensity.
The runner’s high
The study author, Dr Michael Siebers, from the University of Duisberg-Essen in Germany, is one of the lead researchers into eCBs. In 2021 he conducted a study in which a drug that blocks the action of endorphins was administered to 63 runners before they ran on a treadmill for 45 minutes. Despite the absence of endorphins, the runners still experienced feelings of euphoria and wellbeing and a decrease in anxiety – and eCB levels rose significantly (twice as high as when they walked on the treadmill for the same duration).
“Of course, there are likely many hormones involved in this process, but we believe eCBs are the primary ones responsible for the runner’s high,” says Siebers.
While the runner’s high is often portrayed as a rapturous experience, Siebers – a runner himself – says the symptoms can often be more subtle: “People tend to feel calmer in their minds during, and especially after, running,” he says. “I believe a key characteristic of the runner’s high is its capacity to help us stop overthinking and ruminating.” (That’s why, he says, he often goes for a run before a presentation or a stressful day.)
Stuart Biddle, professor of physical activity and health at the University of Southern Queensland, agrees that the idea of an ecstatic high may have been overplayed. “Some may experience it, but it’s not common,” he says. “’Feel good’, yes, but a ‘high’, I’m less convinced.”
Go hard or go home?
The fact that walking did not elicit feelings of euphoria raises the question of intensity. According to Siebers, an intensity of 70-85 per cent age-related maximum heart rate is most likely to elicit an eCB-derived runner’s high. But, he says, it’s not clearcut. “Some research has shown that increases in eCBs are higher when people are exercising at their preferred intensity, compared to when the intensity is prescribed to them,” he explains. “Conversely, a study involving women with depression found no rise in eCBs after 20 minutes of cycling at a self-selected pace, whereas there was a rise when they worked at a prescribed intensity.”
Interestingly, the serotonin response to exercise also seems to be affected by how autonomous exercise is: feeling forced into doing it, or doing more than you feel comfortable with, can have the reverse effect. This emphasises Lubans’ point about neurobiological mechanisms overlap and interacting with psychosocial ones.
For Biddle, running at a moderate effort level is better than a more vigorous intensity for it to be pleasurable at the time. “While people often report feeling good after intense exercise, a positive effect on mood during exercise comes from moderate effort for the vast majority,” he says. This may be because high-intensity exercise doesn’t shift attention towards pleasant thoughts and away from negative ones in the way that more palatable paces do.
The sum of the parts
In the large-scale Mappiness study, 22,000 people were contacted twice a day for six months – at random times – via a specially designed phone app, to find out where they were, what they were doing, who they were with and how happy they felt (a research technique called Ecological Momentary Assessment, or EMA). The results revealed that running, playing sport or exercising significantly raised levels of happiness. So did being in natural green or blue environments. So did spending time with friends or loved ones. Surely putting them all together triples the happiness factor?
Rogerson, ever the objective scientist, points out that while these different strands can and do intertwine, we cannot claim that the whole is always greater than the sum of its parts. “For example, if you run with a group, rather than alone, you might benefit less from the calming restorative effects of nature; but the social interaction would still likely leave you feeling better,” he explains. “Intensity is another factor. If you run at 60 per cent effort, you are likely perceiving the environment and getting the benefits of green exercise, but at, say, 80 per cent, you might be getting a better workout but you’ve got the blinkers on.”
If, like Mike Elcoate, you’re a nature lover who is concerned about environmental issues like the reduction in numbers of birds and insects, degradation of habitats and effects of climate change, running outside can sometimes be a bittersweet experience. “Eco anxiety is the flipside of being environmentally aware and noticing what’s around you,” says Mike. “I have turned my concerns into action, joining The Green Runners, a growing community of runners that take action in the face of the climate emergency.”
Running, and what we experience through it, affects us all differently when it comes to mental health. What boosts us – say, a challenging interval session – one day, when we’re feeling full of energy and confidence, may not the next. That’s why it is important to observe your own responses and feelings during, and after, running. They may not always be what you expect. I tend to think of myself as a solo runner, but often I find the fun and banter of group sessions leaves me with the biggest smile on my face. (That said, 11 out of the 22 studies showing a single run could elevate mood involved running on a treadmill, reminding us of the power of running in and of itself on mental health, regardless of company or setting.)
It’s only been since Jon swapped solo running for being part of a group and shifted his focus from fast times to fun and enjoyment, that he has come to realise that many of the benefits of running aren’t a direct result of putting one foot in front of the other; they’re more akin to positive side effects. He has a piece of paper, on which he has written the four so-called ‘feelgood hormones’, and what activities they are associated with. Endorphins = exercise; laughter; music. Serotonin = nature; sun exposure. Oxytocin = socialising; helping others. Dopamine = achieving goals; treats. “I get all of this through running,” he says.
Three Ways to Add Smiles to Your Miles
Boost your brain chemicals
Listen to music you love: “The brain responds to music it enjoys with a powerful adrenaline, dopamine and endorphin rush, all of which energise effort and alleviate pain,” says McGonigal. If you don’t like to run with music, you can listen before you go out.
Just add water
Run by a river, canal, lake or ocean. The Mappiness study, mentioned above, found that people were consistently and substantially happier when they were outdoors, in natural environments. But aquatic and coastal environments topped the bill. Other research suggests that people tend to exercise for longer in the presence of water.
Find your tribe
Numerous studies have found that exercise adherence (which is key to getting its myriad mental and physical benefits) is better when people work out together, rather than alone. But research at the University of British Columbia shows that this only holds true when people feel accepted by and connected to the group to which they belong. The way exercise is delivered can also determine its effect on your mood and mental health, says Lubans: “Compare the impact of a critical, demanding coach or instructor to a supportive, fun one.”
Runner’s World, November 2024