I do something very similar (although with an approach that is different) and I find that doing harder intellectual work has to be balanced by doing harder phys

I do something very similar (although with an approach that is different) and I find that doing harder intellectual work has to be balanced by doing harder physical work (roughly speaking). As an example, some of my recent intellectual work (and "distractions") included writing a book on Haskell web development, building out a product, some Android contracts and casually reading new papers. This is balanced in my life by training to compete at a professional athletic level (beach volleyball/high jump training. Roughly: Oly lifting, sprint workouts, plyos, etc) and music (Playing drums, guitar, bass and covering songs on my own). Both training for athletics and playing music have a mental states that lend themselves to "recovery" from intellectual pursuits.