Talk to any long-term runner and you’ll hear the same thing: running changes lives. I started jogging at about 15 but only really got into running seriously a decade later, and it’s impacted just about every part of me. Not only am I fitter at 35 than I was at school, but my body has physically adapted to being able to run on concrete and charge up hills. Mentally too, I’m sure that running has had a profound influence on my memory (I plan longer routes before I set off but never use Google Maps once I’ve left home), mood and problem-solving.

But how does running actually change our bodies, from a scientific point of view? And how long do you have to run to start noticing those changes? Well, it’s worth looking at two key aspects: musculoskeletal adaptions (muscles and bones) and changes to the brain.  

“Running is highly beneficial for the musculoskeletal system, causing adaptations that strengthen our bones, muscles, tendons and joints,” says Laura Wilson, physiotherapist and founder of The Swiss Touch. Because running is a weight-bearing activity, she goes onto explain, one of those adaptations is something called bone remodelling. “That’s a process in which older bone issue is replaced with new, denser bone – reducing the risk of fractures (particularly in the legs and spine) and conditions such as osteoporosis as we age.”

Running is also really repetitive; it involves putting one foot in front of the other again and again, and that can build strength and endurance in our quads, hamstrings, calves and glutes. Then, Wilson says, you’ve got the all-important tendons and ligaments, which play a crucial role in joint stability. “Those adapt by producing more collagen, increasing their resilience and reducing the risk of sprains and strains.” 

Think that running is bad for your knees? Think again. “While excessive impact can be detrimental to our cartilage, moderate and consistent running helps improve nutrient flow to joint cartilage, contributing to its durability and overall joint health,” Wilson confirms.

Oh, and we also can’t forget that running has significant benefits to offer the upper body too. It might not be enough to develop lots of muscle in our arms, back and shoulders, but Wilson flags that our core muscles have to work hard to stabilise us as we move, while that rhythmic arm swing also contributes to upper body coordination and endurance – particularly in the shoulders and arms.

So how long do you need to run for to see any of these benefits? Well, Wilson says that neurological changes like improved muscle coordination and running efficiency actually kick in within weeks of taking up the sport. You’ll notice small improvements to muscle strength and endurance in four-to-six weeks but significant muscle development can take a couple of months. “Changes to your bone density occur gradually, often taking months or years of regular running to become measurable,” she says. “Even then, you won’t feel your bones becoming stronger but the long-term reduction in fracture risk is still a significant benefit.”

To reap those rewards, you want to be running two or three times a week; any more than that can increase both fitness and risk of injury.  

Clearly, the physical benefits of running are huge and pretty quick to kick in. And so too are the mental adaptations that regular jogging can cause. Dr Josephine Perry, sport psychologist and author of The Ten Pillars of Success: Secret Strategies Of High Achievers, tells Strong Women that not only does running give us structure, purpose and motivation, but it also alters the way we process and respond to emotions – helping us to better deal with anxiety, depression, connection and self-esteem.

“If running becomes something you enjoy, we know that it can help prevent depressive periods kicking off. A study in the American Journal Of Psychiatry looking at over 33,000 people suggested that 12% of new depression cases could be prevented if the whole population exercised for at least one hour per week. And a study lead by Duke University found that if depression has already been diagnosed, cardio exercise (like running) is as effective as taking anti-depressants, decreasing depressive symptoms in some patients by as much as 70%.” 

Depression aside, Dr Perry says that cognitive health drives the key elements of your mental functioning; how you process your thoughts, memory, ability to pay attention and concentrate, creativity and how well you plan and problem solve. “The biggest causes of cognitive decline are ones we have no control over (aging and having the APOE e4 gene) but sleep, exercise and a sense of purpose are three ways we can work to improve it,” she explains. “Running works well for cognitive health: a review of studies evaluated by researchers at UCLA found those with a higher fitness level are better at paying attention when needed and processing information faster.”

As with those physical changes, some mental adaptations kick in sooner than others. “Some benefits can feel pretty immediate – the improvement in our self-esteem might kick in as soon as the first fitness benefits are felt,” says Dr Perry, who goes onto say that we people who exercise regularly and have good cardio fitness tend to have higher self-esteem. 

“Other benefits, however, will take longer,” continues Dr Perry. “We know on average it takes 66 days to make something into a habit and some of the benefits of running will be seen more once it’s become routine. Habitual running will give you a sense of structure and purpose and as well as social benefits; when you are more active and engaged with others, your quality of life increases. Studies have found that being more social doesn’t just improve life satisfaction but may also extend your lifespan.”

It’s probably worth saying here that, of course, there are plenty of runners out there who jog daily or run marathons and still experience depression and other forms of poor mental health. Running isn’t a cure but more a toolbox for maintaining and building good mental habits – many of which can help to deal with flare-ups and negative thought patterns. Dr Perry also says that you can squeeze more brain changes out of your workout if you focus on pushing beyond your comfort zone. “That’ll help you to improve, whether that’s running faster or further – both of which can really help to improve your self-esteem and confidence. But many of the psychological and cognitive benefits of running will come from the process of going outside, moving your body and pushing yourself regularly.” In other words, just doing the damn thing is enough to make change.

1. Try the occasional naked run. No, that doesn’t mean running starkers through the park (that’s nude running – something else entirely). This is about running tech-free, without tracking or music. “Just notice what is around you and enjoy the feeling of the movement without the fear of self-judgement,” Dr Perry recommends.
2. Set a goal on certain runs. Once a week, give yourself a time or distance goal to aim for. That way, you’ll have some way of measuring and celebrating improvements.
3. Find a run buddy. “Research has found that runners who have a training partner stick better to their to training (as it increases accountability), have improved technical skills and enjoy training more. It also boosts confidence as training with others provides loads of opportunities to give praise and to receive it.” 

Images: Getty