For most of my life, I have been a five to six-hour sleeper. I have to say that I walk/run a few times a week and the physical part of it puts me to sleep, no matter what my brain is telling me.
When my head hits the pillow, I am done.
I did have a stretch of a month or so when I didn't sleep as well, but, I had broken a leg bone. For me, my body craves physical exercise, but, of course, everyone is different. On my off days, I like to meditate and although relaxing, I feel like it works in a different way.