For me I dont count "normal" levels of exercise (4-5 mile run or hard gym workout) but if I do go above that I do eat more. Not because I "deserve" to, but because I NEED to. Otherwise I am not as strong at my next workout, I feel lightheaded and all I can think about is food. Eventually I would get sick. If I run 10-12 miles, I am burning about 1200-1500 calories. I cant get by without eating extra that day, but I dont try to be precise.