This article is from the Aerobics Fitness FAQ, by firstname.lastname@example.org (Robles) with numerous contributions by others.
Consider that you will probably burn between 300 and 450
kCal in an aerobics class. Keep the caloric content of the
meal below that if you're intending to lose weight. That
pretty much lets out any sort of "heavy" meal. The average
American's diet is very high in protein, and relatively low
in complex carbohydrates, so complex carbs before an aerobic
workout are probably better. Keep the total calories from fat to
25% or lower, in general.