I often hear people say that the brain is like a muscle, using it makes it stronger, but also wears it out. If that's the case, the programming is like going to the gym 8 hours a day. Now I wouldn't say that my brain is the metaphorical equivalent to Dwayne Johnson, but I would say that he and I both get tired out after working too hard. I'm not sure what Dwayne does in his pastime (if he has pastime), but I do know that I like to do a few things. I like to play video games, or read a book, or watch some fireship on youtube (really, that guy is the king of programming content in my opinion). Everyone has some way of just relaxing and zoning out when their brain is overworked and I think it's a fascinating thing.
I don't think having a zone-out pastime is really an escapism method because I know I don't mind my life all that much. I also don't think it's a laziness thing because I naturally balance pastime and work-time in my life without much struggle. I think maybe it's just a way for the clockwork in our heads to wind itself up again, ready for us to tick it down to a standstill as soon as possible.
I personally like to take out some old book I know I like and begin my nth reread of it. Or maybe play some small video game on my phone for a few minutes (I'm pretty killer at soul knight by now). I especially like games that have an instant autosave feature. That way, I can put it away and then pick up exactly where I left off.
I'm sure those people exist who can just power through the whole day, every day and are either zombies, or full of motivation that eventually leads to burnout. I however, am not, and I find that taking small breaks is an excellent way to 'ration' motivation indefinitely.