"Why does everything have to have a target?" my friend said to me when I was panicking about not having done enough training. "I thought running was the thing you did to relax?" It’s all too easy in the Instagram age of self-congratulation to get into the habit of doing things for the way they look and sound, rather than because you actually enjoy it. Since wellness became the new religion, I’ve been walking around with a lot of targets on my head. Eight glasses of water a day, 10,000 steps, at least eight hours of sleep a night otherwise you’ll contract all these diseases, function at just 20% and cost the economy billions. Nothing makes you more awake than thinking: I’m only going to get five hours sleep if I fall asleep now… I’m going to get four hours sleep if I fall asleep now… And nothing slows you down more than being interrupted as you’re panting up a hill by a voice telling you that indeed you have slowed your pace by over a minute. Obviously, all these things are good for your health but if, like me, you're a bit obsessive, it can end up being counterproductive.