How many laps would a child need to run around the average playground to burn off the energy in a mars bar?

The kids at the Hackathon were surprised to learn the answer: 120!

Last week we took part in an NHS Hackathon in collaboration with Public Health England. The challenge was to build an app that encouraged healthy habits among children. Our idea was called MealSmart – an app that offered healthy swaps for your evening meals, and told you how much equivalent energy you’d saved in terms of playground laps!