Recovery is equally as important as the stimulus IMHO. Give it a shot. There is always something one needs to work on and it changes as life wears on.
I have issues after intense workouts. However, I work 6-3 as a programmer and workout during lunch 12-1. Even without exercise I have always accomplished most of my work in the morning. Being exhausted for a couple hours where I tend to not accomplish much anyhow isn't a big thing for me.