“Distance. One kilometre” says the computerised Strava voice into the wireless headphones. “Time. Five minutes. And 48 seconds.” Almost six minutes? That must be wrong. Please no more than five. It felt fast. Suddenly my calves start burning. My lungs tighten. Psychologically defeated by an app. Nine more of them? There’s no way. I could just do 5k. I didn’t sign a binding contract before I left the house. No one will know. There are those...