| Hi Barb,
I think it really depends on the individual and his or her schedule. The most important thing is to pick a time that you can make available with regularity. By making exercise a regular part of the schedule, you are more likely to stick to it.
Now, with that said: Much of what I have read suggests exercising before mealtime. Supposedly it helps reduce appetite.
I generally ignore that suggestion. Exercising in the evening, after dinner, works better for me.
Whatever time you choose, be sure to monitor closely. Often, I find it necessary to have a snack before bed on nights when I work out.
Travis | 
