Walking v running: For the same distance, which consumes more energy?

Walking and running affect the body in different ways, even when covering the same distances. Here’s the science behind it. It’s Monday morning, the alarm goes off and it’s already 7.

30am - and you’re 30 minutes late. Normally you need 45 minutes to walk the 3km to work, but this morning you’ll be running for 20 minutes. Yes, but by lunchtime you’re feeling more tired and you have the impression that you’ve expended more energy than usual on the trip.

Yet you’ve covered the same distance as on the other days. How can this be? The calorie expenditure associated with any activity is called the “metabolic cost”, and corresponds to the energy consumed by our organs to cover a given distance. This metabolic cost can be determined by analysing the oxygen our bodies consume and the carbon dioxide they produce, we can estimate the amount of energy expended, and thus the metabolic cost.

It was using this method that researchers had already answered our question back in the 1970s..