cardio is good in the morning because it burns the stored fat rather than burning the calories you've eaten from the whole day. Working out in the morning, on an empty stomach, is not a good idea. You need energy (speciffically carbs) to burn during a workout. I realize alot of people workout in the morning but you should get something to eat atleast on hour before your workout. If I have to workout in the morning I wake up an hour and a half before, get the something to eat, and then I go back to sleep untill it's time to workout. I don't know your weight, stats, or goals so I can't give you any amount of protein, carbs, or fat you should be getting in one day. List them and I'll try to help out. You can loose your lower "belly" if you do cardio, but you should build up the muscle too. Make sure you work your abs about every three-four days.