Why does running make you feel so good?

Ok, ok, not ALL the time, but the runner’s high is a real thing, and with over 858,000 people downloading the NHS couch to 5k app in lockdown 1, there must be something going for it! There are many elements that make running positive for your mental health, and it is increasingly being seen not only as great for the body, but for the mind too. So what is it about running that makes it so good for your brain and mood? Let’s look at the science.

The runner’s high is a real thing!
  1. brain imaging study on endurance athletes and healthy controls at rest showed an increase in coordinated activity in some brain regions involved in executive functions (decision making) and working memory. They also found a reduction in ‘default mode’ activity – what our brain does when distracted, i.e. nothing very useful. This part of the brain is also linked to clinical depression, showing one pathway by which consistently running may reduce depressive tendencies and improve brain health. Interestingly, these are similar results to those seen in meditation – while running you’re turned into your surroundings, and what your muscles and breath are doing, not worrying about work, family or other stressors. So, running could be seen as a form of ‘active/moving meditation’.
  2. Another study in mice showed that exercise breaks down a stress-inducing molecule Kyneurenine. The molecule itself builds up when you’re stressed, and can enter the brain, causing stress-induced depression and anxiety in some people. During exercise, there is a build up of an enzyme able to break down this molecule in the muscles, meaning it’s unable to enter the brain, protecting it against stress-induced depression. 
  3. Beta-endorphins are released in running, improving mood post-run. The hormone is generally used by the body to reduce stress, and, as an endogenous opioid, is also linked to reducing pain. This happens not just over the course of one run, but also over the space of several months, meaning that the effects can last long after you’ve ended a run. This is potentially the source of the elusive ‘runner’s high’, which usually starts to kick in after 30 minutes of running. It’s also one of the reasons that runs can feel very hard at the beginning but get easier throughout – pain relief and a reduction in anxiety are both side-effects of our body’s reaction to exercise. 
  4. While endorphins have long been credited for the runner’s high, it is likely that endocannabinoids play an even larger role. These are small enough to cross the blood-brain barrier (unlike endorphins), and act on the same receptors and systems that THC (the active ingredient of cannabis) does. This triggers feelings of euphoria, a sense of calm and reduced anxiety. There’s still a lot of research in this area and the mechanisms in humans still aren’t quite ironed out, but it looks promising!
  5. Running (and exercise in general) also acts as a buffer to life’s stressors. In the same way that stressing out the body through exercise can lead to physical adaptations to cope, it can also lead to mental adaptations associated with resilience, which are then transferrable to other areas of life. Regular runners tend to be better able to cope with stress, thanks to the effects of
  6. In rats, high intensity aerobic exercise such as running has been shown to literally create new brain cells. Up to a limit, running stimulates an increase in grey matter in the brain (beyond that limit, grey matter temporarily decreases, e.g. in extreme multi-stage endurance events – not surprising if you’re running 4,487km like those in the study!).
  7. There are other endogenous benefits of running that may benefit the brain through indirect means, such as improved insulin response, improved immune function, improved circulation (including to the brain), increased energy levels, better sleep and improved focus (including the ability to multitask better!). 
  8. Tangential mental health benefits of running include having a feeling of community (the running community is like I’ve never experienced before), having quantifiable goals and the sense of accomplishment that comes with that, which is transferrable to other areas of your life. Running has been shown to improve your self-esteem – placing the focus on what your body can accomplish and how it feels rather than what it looks like is one of the best to move away from being sucked into diet culture and the constant drive to lose weight. 

Evolutionarily, this all makes sense. As hunter gatherers, we would have had to chase prey for any miles, and having adaptations to a) make that feel good and b) reduce pain on long runs would have meant we were able to run further. And enjoying the chase/run would have meant more food for everyone, so better survival.

It’s important to note that many of these studied were either done on animals, or in small numbers of volunteers. However, anecdotally the benefits of running for the brain are multi-fold and substantial, and it’s great to see this backed by multiple studies. Hopefully we’ll start to see more of this in the coming years as the link between physical and mental health becomes increasingly clear. 

While these benefits mainly pertain to running, it’s also possible to get many of the same benefits through other forms of aerobic and anaerobic exercise. The benefits may be to differing degrees, but the important thing is that you find a form of movement that is enjoyable and sustainable for you – there’s no point in overdoing it on a sport that you hate. Moving your body in whatever way feels best is a good place to start! And if you’re just starting your running journey, keep it up! It is always hard at first (and at second, and at third), but the benefits are SO worth it. If you enjoy this topic, check out the book Endure by Alex Hutchinson. It’s fascinating and delves into the science further without being hard to read. 

If you regularly read and enjoy my articles, please consider making a small contribution to the running of my blog. If you’re looking for a little challenge to focus on for your training, why not join in our 5k time trial challenge at the end of March?

What does ‘sustainable’ even mean?

It’s rare that a term becomes such a key part of common lexicon in such a short space of time as sustainability. The term itself is derived from the Latin ‘sustinere‘, meaning ‘to maintain’, ‘to hold’ or ‘to support’. The word can now be found used widely in policy, commerce and economics, usually in a way that pertains strictly to environmental sustainability

It’s become widely used in the last 30 years in spite of (or perhaps because of) its multitude of potential definitions. For example, this catch-all term can be found explaining why you should buy a new dress, why a city council should build new properties or why a brand’s coffee is better than other coffees. But what does it actually mean?

Around 30 years ago, the World Commission on Environment and Development published Our Common Future, charting a path for development that “meets the needs of the present without compromising the ability of future generations to meet their own needs.” This is essentially our current definition of environmental sustainability. However, the term has since come under fire for lacking any unified, definitive or quantifiable meaning – basically, it means nothing.

There is no doubt that the fashion industry requires movement in a direction that manages its demands on the environment without compromising what’s available for future generations. No one would argue that the fashion industry, responsible for 10% of global emissions, doesn’t require more investment in ‘sustainability’, but without any quantifiable definition of the term, what does this look like?

Various other terms within many industries are verified using third-party certifications and accreditations, meaning that a brand or business has to prove it is doing something to be able to use the term. The Soil Association, for example, is a UK-based charity that regularly reviews manufacturing processes throughout the supply chain to ensure a business is producing organic products. You cannot use the term ‘organic’ without being certified. The Global Organic Textile Exchange (GOTS), does the same for textiles, showing the buyer that the products throughout the supply chain have been verified by an external body as organic.

One issue with sustainability within the fashion industry is that almost all accreditations are voluntary. Rather than having regulatory standards, similar to those within the food industry and mandatory energy labels on EU white goods, accreditations are seen as ‘optional extras’, often used as a marketing tool rather than a baseline standard.

Because of this erosion of state power, brands and organisations within the fashion industry looking to become more ‘sustainable’ are left in a state of ‘choice paralysis’; there are a multitude of private-sector accreditations which all claim to provide certification of ‘sustainability’ in marginally different ways. And of course, because they’re private sector, all claim to be slightly better than their variants, yet none are government regulated. This isn’t to say they don’t all provide some benefit – many do in considerable ways – it’s just that the whole industry is open to confusion and lack of regulation, to the point that the consumer has a very hard time understanding what they’re buying into. 

Various voluntary initiatives available to the textiles industry – but by no means all of them

So what can we do?

With WOVN’s 2020 consumer report showing an 84% increase in the use of terms such as sustainable, ethical, Fair Trade and eco-friendly and an increased desire to shop from brands seen as ‘sustainable’, it’s important now, more than ever, to understand what this term really means. As brands cotton on to this fact, there’s an increasingly opaque arms-race to appear more sustainable, where being truly environmentally conscious is almost secondary to appearing as such.

There have been calls to incorporate ‘Carbon Labelling‘ on clothing, but of course being sustainable isn’t about simply releasing as little carbon as possible (in the same way that the health of a food item isn’t about being as low calorie as possible), but also things like wastewater reduction, ceasing the use of harmful chemicals, improving labour standards, using renewable materials, reducing waste textiles and so much more. While innovative, labelling like this would only solve a proportion of the problem, and potentially just become another method of greenwashing.

Accreditations will play an important role in the fashion industry’s road towards becoming more in balance with the environment, but there are serious changes that need to happen, including regulation of the regulators. Consolidating numerous similar accreditations into larger, stronger and more rigorous ones would be a powerful first step. 

Secondly, as a globalised industry, fashion requires international regulation. The majority of the textile industry has outsourced its negative environmental and social impacts to the Global South, affecting the people and habitats that can least afford to protect themselves, all the while making masses of money for the corporations residing in the Global North. This inequality simultaneously exacerbates the issues and hides them from view of the consumer. This means that it’s hard to know how what you’re buying is impacting the people who made the clothes, for better or worse. Because of this, we need international regulations throughout the supply chain, protecting both the environment in the world’s most biodiverse areas and those most affected by the industry’s indiscretions. 

In the meantime, companies must be more transparent about their supply chains, allowing the consumer to make their own decisions about what is ‘sustainable’ and what is not. After all, no brand is going to be perfect in all regards, certainly not while industry accreditations are such a minefield. It should be possible for the consumer to decide what matters most to them, and be able to accurately measure up brands to this standard. It is important that this doesn’t automatically disadvantage those choosing to become more transparent; while transparency may highlight areas requiring improvement, brands that choose to avoid transparency for fear of what it may show up should be penalised beyond those showing up less favourable elements within their supply chain. This is important because transparency is the first step towards accountability. Brands that doesn’t show the former will never have the latter.

Consumers, while requesting greater transparency and action from the worst offenders, should also realise that no amount of sustainable production will counteract buying clothes we don’t need. Buying less overall, buying secondhand, fixing what we already have and finding new homes for clothes we no longer wear will always be better than shopping, even from ‘sustainable’ brands. 

Further up the chain there should be incentives and clear direction for brands wanting to do better. This direction should be passed on to suppliers, with brands using their purchasing power to push suppliers to be better, and workers using unions to effect chain from the ground up. Large brands and conglomerates especially have huge amounts of power to effect change, and it’s time they were forced to do so. 

Over over 300,000 tonnes of clothing ends up in landfill in the UK each year – no matter how sustainable the brand, this can never be environmentally friendly.


  • There are many steps available to brands looking to become more sustainable, in whichever way they choose to interpret the term.
  • However, without quantifying what sustainability actually means, it’s going to be difficult for the fashion industry to ever reach the goal of being ‘more sustainable’ in any meaningful way.
  • Currently there is a mishmash of private-sector accreditations and certifications all with overlapping goals being regulated with varying degrees of success. Without unifying these standards and consolidating the accreditations that exist, it will be hard for consumers to be able to assess which brands are truly sustainable vs which are using accreditations as a facade.
  • As the fashion industry is a global one, it requires global regulatory bodies, which currently don’t exist. Currently it is beneficial for brands to outsource their labour and environmental harm to the Global South, which doesn’t have the resources to protect itself. International regulation could limit this harm.
  • In the meantime, brands should improve transparency of their supply chains to allow consumers to choose who they want to buy from. Brands should be congratulated for improving transparency, although not at the expense of action which is the obvious end goal (H&M is one of the most transparent brands but also one of fashion’s biggest polluters – transparency can’t come at the expense of action).
  • Consumers have the power to request greater transparency from brands, and also to stop buying from the biggest polluters. Shopping small businesses is a great place to start, but we should only buy what we really need. No amount of sustainability will make up for purchasing a wardrobe of clothes you never wear.
  • Large brands have huge amounts of purchasing power and are in a strong position to effect change. It’s about time they did so.

If you enjoyed this blog post and would like to read more, there is a great report on palm oil, fishing and textiles, all of which suffer the same lack of unified regulation – you can read it here. If you regularly read and enjoy my articles, please consider making a small contribution to the running of my blog.

March 5k time trial challenge


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Home training & faster 5k plan: https://www.rushbynature.com/shop/home-training-amp-a-faster-5-10k

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Happy training!