There's a state I think of as the zombie: never properly asleep, never properly awake. The way out isn't waiting for sleep to turn up on its own. It's earning it, and the research shows exactly how.

An engine that only ever idles down to the shops doesn't get an easy life, it gets a shorter one. Bodies work the same way. Why pottering isn't the safe option after 50, and what hard enough actually feels like.

The Virtual Village Hall closes on 11 September. If the live classes and friendly faces were the bit you loved, here's where to find them again, starting with two free workouts a week.