"It's mental until you pass out, then it's physical" - Unknown
You should always run in the morning because after that hour by hour something always needs to be done and the day gets away and suddenly that "oh my gosh! I'm running out of daylight" then panic....what time does the gym close? Geez....then another, "something to do" When its all said and done you're just too tired to go anywhere. Yep! That was my big running/non-running day.