> If one has a good sit/stand desk and spends a lot of time coding while standing, 10 minutes lying on a bed is incredibly replenishing for example.

Pomodoros[0] are life changing. While writing a paper/fiction/code/anything, I force myself to take that break; even if I'm on a roll. Sometimes I leave myself a note "When you get back, solve this particular problem/write this particular part" or I'll scrawl some shorthand solution for the problem on my whiteboard. I'm way way more productive if I do anything else for 10 minutes, whether it's laundry, video games, lying down, reading fiction... doesn't matter. It's almost like my brain is working while I'm relaxing.

[0] - https://en.wikipedia.org/wiki/Pomodoro_Technique