How Many Calories Does Running Burn?

Runners looking at fitness trackers
(Image credit: Shutterstock)

You may be pleasantly surprised to discover that the question “how many calories does running burn?” has an easy answer.

It’s about 62 calories per kilometre or 100 per mile. Unfortunately, it’s an answer that’s effectively useless when applied to individuals in the real world rather than under laboratory conditions.

Calorie burn during exercise is based on a whole range of factors. For running, your weight and height are key, which is one reason fitness trackers ask for that info when you set them up. Then you have to consider things like the pace you’re running at, the incline and terrain you’re running on, and the weather you’re running in.

Heavier people burn more calories, and running hard up a muddy hill naturally burns more than jogging along a flat road with the wind behind you. Your heart rate is a reliable indication of how hard you’re working, and thus how many calories you’re burning, so you get better estimates of calorie burn from trackers that have a built-in heart rate monitor, although a chest strap is much more accurate, as we discovered while researching the best heart rate monitors.

If you don’t use a fitness tracker, you can use a calculator like this one on ExrX.net to get a better idea of how many calories a run burned. Broadly speaking, the estimate of 62 calories per kilometre is more like a minimum of what you can expect to burn while running if you weigh 50-60kg. If you’re around 90-100kg, or working very hard to run fast, into the wind, or up hills, it’ll be more like 80-100 calories per kilometre.

Like we said, complex and not particularly helpful. Perhaps the more useful question is not about calorie numbers but simply: “Is running a good way to lose weight?” And the easy answer to that is that running is an absolutely terrific way to lose weight, although it’s a little more complicated than just trying to burn as many calories as possible.

Thankfully we have some excellent advice on running for weight loss from Dr Justin Roberts from Anglia Ruskin University’s Cambridge Centre for Sport and Exercise Sciences. Roberts suggests that if you’re new to the sport, it’s best to start slow.

“If someone wants to lose weight, I would probably recommend lower intensities, but with some high-intensity work – things like interval runs or tempo runs,” says Roberts. “If you’ve got someone who’s quite new to running, I wouldn’t throw them in a high-intensity programme from day one. I’d opt for a slower run – what we call fatmax training. Technically it is maximal fat oxidation and the intensity this occurs at is called the fatmax intensity, which can be correlated to heart rate. It will differ between people, with fitter people tending to have a higher fatmax.”

That’s one of the advantages of running as an activity. It lends itself to both low-intensity steady state (LISS) cardio, which you can do regularly for long periods (as long as you build up your endurance in sensible fashion), and high-intensity intervals, which require you to work close to your max heart rate. You’ll probably find running one of the best exercises for spiking your heart rate to 80% of its max. That’s not an easy thing to do, and many people doing HIIT workouts in the gym might well find they don’t raise their heart rate more than they would do in a typical run if they tracked it closely.

When all’s said and done, it’s best not to run to just burn calories – it’s best to run because you enjoy it (and even if you don’t when you start, give it time, because a lot of people who aren’t keen at first end up enjoying it). You can burn loads of calories and drop kilos of bodyweight whether you’re running, lifting weights, doing HIIT or playing Quidditch – the most important thing is that you enjoy it and want to continue doing it, because it doesn’t really matter how many calories a single workout burns if you never do it again.

The other thing to consider about running and calories is that when you’re following an intense training regime ahead of something like a marathon, you might actually find it hard to maintain weight owing to the amount of running you’re doing and calories you’re burning. In those situations it’s vital to fuel your marathon training smartly, so you get what you need without opting for huge unhealthy meals because you’re constantly hungry.

We spoke to Tim Lawson, director and founder of sports nutrition brand Secret Training, for advice on fuelling your training. The key takeaways were to focus on a healthy diet (more veg and less booze is a good starting point), not overdo your carbs, plan your recovery meals in advance and consider supplements if you’re finding it hard to consistently get what you need from your diet alone.

Nick Harris-Fry
Senior writer

Nick Harris-Fry is a journalist who has been covering health and fitness since 2015. Nick is an avid runner, covering 70-110km a week, which gives him ample opportunity to test a wide range of running shoes and running gear. He is also the chief tester for fitness trackers and running watches, treadmills and exercise bikes, and workout headphones.