Fitbit is a nifty bit of tech, but lacks nuance. On the face of it, Monday was a good day for fitness with no less than 14 hours 27 minutes in “exercise zones”. Don’t you believe it. Data needs interpretation.

I’d had my Astrazenica jab on Sunday and been warned that there might be some short-lived side effects. Sure enough, 24-hours later I started to feel achy and my heart rate shot up to around 120 bpm. So where it says “fat burn”, it should say “lying on the sofa feeling like death warmed up” and where it says “cardio” it should say “lying on the sofa in acute discomfort having decided not to risk A&E”.

The fact, of course, is that my body had gone into defensive mode in response to a percived attack from the vaccine, which is exactly what it should have been doing. After another 24-hours it was fine.It’s just a question of keeping youre nerve.