Skip to Content

What does running do for your body? 10 benefits of running


Many people will tell you that their life changed when they started running.

So if you’re thinking about starting running, then you may be wondering: “What does running do for your body?”

Running has many physical and mental benefits – from the so-called runner’s high to better heart health and weight loss. 

But what exactly are the positive effects of running on your body? And are there any negative effects that you should know about?

In this guide we’ll explore:

  • What does running do for your body?
  • What does running do for your body shape?
  • 10 benefits of running
  • Are there any negative effects of running?


Let’s get going!

what does running do for your body

What does running do for your body?

At the start of a run

As soon as you head out of the door and start running you will notice changes in your body.

  • Your heart will pump faster to push blood around your body. 
  • Your breathing rate will increase as your lungs suck in more oxygen. 
  • Your body temperature will rise and you will start to sweat.

In other words, your heart, lungs and muscles will all work harder to support your body during exercise.

At the same time, blood flow to your other organs, such as your intestines, will decrease. 

It is because of these changes, especially at the start of a run, that many runners feel that the first mile of a run is the hardest. 

Related: Walking a mile a day: Benefits + 7 tips to get you started

During a run

Eventually your body will acclimatize – but how soon depends on your fitness levels and running experience.

If you run regularly, your body will soon stabilize.

If you’re new to running, it will take a little longer for your body to catch up.

Once your body acclimatizes to the run, you will soon hit your stride and your run will feel less gruelling. 

Your body will release ‘feel good’ hormones (called endorphins) which will provide you with the necessary energy to keep moving your body.

These hormones are what stimulates the ‘runner’s high’ feeling that many people experience when they exercise or go for a run.

Depending on your fitness levels, you will be able to run for miles and miles before tiredness and fatigue sets in. 

If you push yourself too far, you may start to experience heavy legs syndrome as lactic acid starts to build in your leg muscles.

This is your body’s way of telling you that you’ve pushed yourself too hard and it’s time to slow down. 

Related: Is running in place effective? Benefits + 3 sample workouts

what does running do for your body

After a run

Post-run your body will continue to release ‘feel good’ hormones so you will still feel energized.

Various studies have shown the positive effects of exercise on your mood during and after a run.

According to John Hopkins University School of Medicine, exercise increases the levels of endocannabinoids in the bloodstream. 

Endocannabinoids are mood-improving neuromodulators that promote short-term psychoactive effects such as reduced anxiety and feelings of calm.

The key takeaway? Running will make you feel good not just during a run but for hours afterwards.

Related: Should you work out on your period? 6 best exercises to do on your period

During recovery

During the recovery period – in the 24 hours after your run – your body will continue to burn calories as it repairs muscles and clears lactic acid.

This process is referred to as the ‘afterburn effect’ (also known as post-exercise oxygen consumption – EPOC).

The ‘afterburn effect’ is often much larger after high intensity exercise like interval training or hill sprints.

However, one study confirmed that prolonged exercise when performed at intensities above 40% to 50% of VO2 Max can trigger the metabolic processes responsible for the ‘afterburn effect’. 

During the recovery process you may also start to feel some muscle soreness and stiffness (called delayed onset muscle soreness – DOMS).

Do some gentle stretching to help alleviate some of the discomfort.

You may also benefit from foam rolling.

Related: Running a mile a day: Benefits + 9 reasons to do it

what does running do for your body

What does running do for your body shape?

Running brings about many physical, physiological and biomechanical changes in your body.

As you run more and more, you will notice these changes. 

Not only will your endurance and stamina improve, but you will shed the pounds and become more strong and toned. 

Running is a great way to burn calories, but the number of calories you burn will depend on how often you’re running as well as things like your age, gender, height and weight.

The effects of running on your body shape will also depend on your body type.

Body type is linked to the distribution of muscle mass and fat. 

While some people are long and lean and find it hard to gain weight (called ectomorphs), others are curvier and have difficulty losing weight (called endomorphs). 

If you’re lucky and naturally have a strong and athletic build (called mesomorphs), you’re neither underweight or overweight. 

While every body is unique, distance runners tend to have a body shape similar to that of the ectomorph body type – that is a thin frame that is long and lean. 

Related: How to get a runner’s body: Characteristics + 6 training tips

what does running do for your body

Related: How to fix a saggy butt: 5 exercises to lift your butt

10 benefits of running

Now you know what running does for your body, here are 10 benefits of running for the body and mind. 

#1 Improves heart health

If you run regularly you are reducing the risk of heart disease by up to 55%. 

Running helps to promote healthy blood flow, blood pressure and cholesterol. 

It also helps to prevent blood clots from forming in the arteries and blood vessels. 

#2 Helps to burn more calories

According to Harvard Health, running burns the most calories compared with other aerobic activities. 

You can expect to burn between 420 and 495 calories per 30 minutes if you run at a pace of 10 minutes per mile. 

Studies have also shown that intense workouts like interval training and hill sprints are better for burning calories.

This is because high intensity exercise achieves a much greater effect in the same amount of time as an easy or moderate run. 

#3 Boosts your mood

Exercise like running has been shown to improve your mood and reduce symptoms of anxiety and depression.

Running releases endorphins into the body that make you feel good and leave you feeling energised for the rest of the day.

#4 Strengthens and tones your muscles

Running has many benefits for your lower body strength and tones your legs. 

While running builds lower body strength, it does not help to build upper body and total body strength which is important for all round fitness.

So it is recommended you include at least two strength training sessions in your training routine each week so you can develop all body strength. 

#5 Improves your mental health

Running has many positive effects for your mental health.

Some studies investigating marathon training found a positive relationship between marathon training and self-esteem and psychological coping. 

Other studies have shown that runners have better emotional wellbeing, self-confidence, mood, depression, aggression and anger, anxiety and happiness. 

#6 Increases bone density

Running is a weight-bearing exercise, so your legs have to work hard against gravity to propel your body forward.

This helps to develop strong and healthy bones which helps to combat degenerative diseases like osteoporosis.

#7 Improves your memory

According to a 2013 study, consistent exercise like running improves memory function and may help to maintain brain function.

Admittedly, this study was performed on mice and not on humans.

However, it is hoped that, as a result of this study, the identification of the protein responsible for improved cognition may lead to new therapies and treatments. 

#8 Improves your cardiovascular fitness

Running is one of the best ways to improve your cardiovascular fitness and conditioning. 

Typically runners have a low resting heart rate and high VO2 Max which are positive indicators of cardiovascular fitness. 

Studies have also shown that distance runners have larger, thicker left ventricles compared with sedentary people. 

In other words, their hearts are more efficient than those of sedentary people, pumping large volumes of oxygenated blood per beat. 

#9 Encourages healthy habits

When you start a regular running routine this may encourage you to adopt healthy habits in other parts of your life, such as following a healthy, balanced diet or taking up other forms of exercise.

Regular exercise also helps to build healthy routines such as better sleep patterns and getting outdoors more.

#10 Lowers blood pressure 

Running can help to lower your blood pressure.

High blood pressure, if left untreated, can lead to heart disease and other serious health issues.

According to cardiologist Dr. Konrad Grossner: “You need to run regularly if you want to use it to help reduce blood pressure.”

Adding that “it will take around one to three months to start seeing a change in your blood pressure when you start exercising”. 

Related: How to start running when overweight: 12 game-changing tips

what does running do for your body

Are there any negative effects of running?

Now we’ve looked at the positive effects of running, what are the negative effects of running on your body and mind?

Running is not for everyone, and there are some downsides of running that you should be aware of.

#1 Running can cause muscle imbalances in your body

Running mainly focuses on developing your lower body strength.

If you neglect to strengthen other parts of your body such as your core and upper body, this can create muscle imbalances which can lead to injury. 

A strong core, for example, is important as it keeps you strong and stable during a run. 

If your core is weakened, this can lead to issues with your running form and can make you more susceptible to slouching during a run.

To avoid this, make sure you incorporate at least two strength training sessions in your routine each week.

In these sessions, focus on all body movements (also known as ‘compound’ movements) that include the legs, core and upper body.

#2 Running can cause exercise addiction

Some runners enjoy running so much that they become addicted to it and form an unhealthy relationship with exercise.

While it’s good to develop a passion for exercise, sometimes this can go too far and have detrimental effects on your health.

A study from the International Journal of Environmental Research and Public Health identified that people who are reported to be “obsessively passionate” about running were more likely to develop running-related injuries compared to those who were ‘harmoniously passionate” about the sport. 

In other words, runners who are able to mentally recover well after running were less likely to experience running-related injuries. 

#3 Running can cause injury

The prevalence of running-related injuries unfortunately remains pretty high, with more than 80% of running injuries caused by repetitive stress. 

According to a 2015 study, previous injury and use of inserts are risk factors for running injuries.

Wearing the wrong running shoes can also cause problems. 

Listen to your body and if you develop any muscle or joint pain, stop running until you determine the reason for the pain. 

Caroline Geoghegan