Do you use more energy running on a treadmill compared to outside? © Getty Images

Do you use more energy running on a treadmill compared to outside?

Running outside creates drag, but how much of an effect does this have?

Asked by: Glenn Thomas, by email

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Running outdoors requires 
a little extra energy because you’re moving through the air and this creates drag. But the difference is insignificant unless you’re running quite fast. If you can do a mile (1.6km) in seven minutes or less, which is a speed of 8.5mph (13.7km/h), then the difference is about 1 per cent. Studies have shown that running a mile uses about 100 calories, 
so you’ll save just a single calorie if you run that mile on a treadmill. Or you can just set the treadmill at a 1 per cent incline to compensate.


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