If I can hack getting up in the morning, starting the day with a 5 mile quick clip run is fantastic and I feel better definitely afterwards.
On the other hand I like running at night too which can also feel good after a day of work. I tend to sleep better when I exercise either way.
Old man me misses real running and kinda hates you right now.
Going to run a couple miles on indoor track this afternoon and try not to look at mins/mile and maybe concentrate more on not doing 100% of my age groups average max heart rate. I know that's the smart thing to do but damn, it's hard to not look at a slow slough and not compare it to what I ran 30 years ago.