It is best not to eat just before you go exercise, you should probably wait and eat after you exercise. You need to have energy in order to exercise so if you haven't eaten anything yet that day you could eat a protein bar or something. You will burn the calories you just ate for so in order to burn stored fat it's best not to have new calories in your body.
You should not eat a full meal right before exercising. Eat a small snack, like a banana and a handful of nuts, to give you a boost before you work out. It is best to eat a full meal after you work out.