Is three minutes of exercise enough?

Like many, Michael Mosley wants to get fitter and healthier but can't face hours on the treadmill or trips to the gym. Help may be at hand. Using himself as a guinea pig, he uncovers the surprising new research which suggests many of us could benefit from just three minutes of high intensity exercise a week. He discovers the hidden power of simple activities like walking and fidgeting, and finds out why some of us don't respond to exercise at all.