you should eat something with carbs in about half hour – hour before exercise and then have a snack just after exercising(you’ll be starving so a small snack stops you diving into your meal when you do get it)…then a little later eat a proper meal :D
btw…you should be eating at least 6times a day (brekkie,snack,lunch,snack, dinner, snack) although as you probably know the snacks should be low calorie and low fat :)