Timing is much less important than the activities themselves, but I think mornings are most desirable because anything positive you accomplish in that period will build positive momentum for the rest of your day. Hal Elrod's book The Morning Miracle discusses this concept a bit more depth, if you're interested.

I do my exercise first thing in the morning. I wake up, hydrate, brush my teeth, put on workout clothes, and I try to be out the door by 6:30AM. I never thought I was a morning person either, but my body adapted pretty quickly.