I do it in the morning, whatever that means. When I had kids in early-morning seminary, it meant I was waking up at 4:45
(which sucked, especially in winter). Fortunately I no longer have that issue, so I usually wake up 5:15-5:30. For me, it is too difficult to consistently exercise after work, because there are too many commitments and demands, so I just force it to happen before my day starts.