WHAT EXACTLY IS FASTING?

How long do you have to forego food to meet their definition of fasting? “It can take several hours to fully finish the response to digesting a meal,” says Thompson. “The best advice would be to ensure that your last meal was four hours before exercise to get the effect that we reported. Or exercise before breakfast – this is exactly what we did.”

It’s actually less important how you refuel post-exercise, especially if you’re active generally. “This is only really an issue for people who are looking to train more than one time on one day,” Thompson says. “This is therefore important for more serious athletes, but for everyone else, it is probably fine to follow a normal meal pattern without worrying too much about refuelling.”