How do you keep yourself physically healthy and fit? Long-term health, energy and longevity genuinely matter to me in a husband and father.

Which was the funniest answer available and comfortably the worst one, and I knew it while I was recording it.

The correction, which I should have led with: I'm not unfit, I'm unscheduled. I swam competitively at university and I'm still a good swimmer — two screws in that shoulder from an epileptic fall, so butterfly and anything competitive are gone, but swimming isn't. I walk fifteen to twenty minutes uphill to my own front door every time I miss the last bus, which is most nights, and I've never once counted it as exercise. I shifted thirty mattresses on Saturday and didn't need a lie-down. What I don't have is a gym membership, any interest in acquiring one, or the faintest intention of ever jogging.

On medication, since you asked that too and never got an answer either: nothing for the epilepsy — I came off it five years ago and haven't had a seizure since. For the ADHD, Ritalin 10mg six times a day, Concerta 54mg once, and some vitamins. That's the whole list. And before your brain arrives there on its own: the thing that put me in a coma was an antidepressant I should never have been handed alongside those, not the ADHD medication itself. I've been on these for years.

But all of that is a defence, and you weren't asking me to defend myself. You were asking whether I intend to still be here. I know that isn't a tick-box question for you.

So I've thought about it every day since you asked. The habit is the entire battle, and I've been stubbornly opposed to starting one. I've had a good run this year of making better decisions and actually holding to them, so it's time. There's an indoor pool in Seon, close by, heated, cheap. I've signed up. I start on the first of September.

I've promised myself to keep at it until I enjoy it. The reward for managing that is that I'll enjoy it — which is the most efficient incentive structure I have ever designed.

I'll send you photographic evidence from the sessions. And I want to ask something of you: for the first month in particular, deploy every tool at your disposal to ensure there are severe consequences if I miss even one. After a month I'll be in rhythm and I'll almost certainly start going more than I signed up for. It's the first four weeks that need policing — and I'd rather be policed than end up being the man who mentioned a pool to you once.