Outside my window, it’s dark, drizzling and so cold that the rain is freezing on the glass. It’s about as miserable a scene as you could expect from an English winter evening, but as soon as I finish writing this, I’m going to go running in it. Not because it’s healthy, not because it’s fun, but because Nike understands how I feel about exercise, and they apply the carrot and the stick in precisely the right quantities to get me out of the house in a pair of tights at 11pm in sub-zero temperatures. Not bad for a company of people I’ve never met who flog trainers from an ivory tower 5000 miles away.

Let me back up a little bit.

Running is a pretty lonely activity and it can be really hard to get motivated to do it. Sure, you get a nice endorphin rush at the end, but without a strong motivating force to get you out the door, or to tell you to lift your knees or to put in that little extra effort, it’s pretty easy to just say “this is a perfect night for a bottle of wine and an episode of ‘Homeland’ on the sofa with my wife.”