Chad, my problem with headphones walking is missing danger cues (unlike at home). For workouts on torture, er, exercise equipment, absolutely; I have a ‘rowdy’ playlist (of old man songs, largely rock) that pushes me to keep moving.

As to the ‘cumulative’, I’m not an expert, merely a reasonably well-read sleepophile (anyone with better insight?). My understanding is that naps, 15-20 mins, can make up for more than their time asleep. I don’t know how that works, but I don’t think you need 2 hours if you only get 6.

Interestingly, before we had electric light, folks regularly woke up in the middle of the night, read for a while or the like, and then went back to sleep, so it doesn’t have to be consecutive for sure. I think naps attach to sleep deficits. I don’t think you can ‘bank’ sleep, but recently read something making that claim. Not that I’m good at napping, though I can with proper preparation.

When I travel, however, while I try to use food cues and more to try to adapt, I also am prone to over-caffeinate during the day to compensate. If only everyone allowed other substances, because alcohol to sleep isn’t a good approach (not that I haven’t tried :). As always, your mileage may vary.

I’m keen to always try for eight hours of sleep myself, though I’m rarely successful in doing so. A question about the eight hours – that’s cumulative, and not consecutive, right? That is, I can sleep six hours at night, then take a two-hour nap and still have that count as eight hours? Does a nap always contribute to the sleep count of the night before, or the upcoming night?