I'm sure you have heard about all-everything United States swimmer Michael Phelps' legendary diet. According to an article published by FOX News, Phelps consumes 12,000 calories a day when he is training! I'm not going to argue with a guy who just won 8 gold medals in this Olympics. If you burn alot of calories, you can eat alot of calories!
As a collegiate football player, I can remember eating 5,000 plus calories a day in order to maintain energy for the day and play the game. I needed every one of those calories. If I ate that way today, I would probably weigh 500 pounds! Now, I consume 2,000 calories or less each day.
You must burn more calories than you consume (caloric deficit over time) in order to lose weight and burn body fat. This is the law of thermodynamics. Even if you are a "workout warrior," the law of thermodynamics still apply. You cannot eat as much as you want (or maintain a caloric surplus) and still lose weight. If you exercise regularly, it will be easier for you to maintain your caloric deficit.
Looking at Michael Phelps' cut body, he needs every one of those 12,000 calories to fuel his amazing success in the swimming pool.
Do you know how many calories your body needs to support your daily activity and exercise? Do you know your basal metabolic rate (BMR )? You will need to know your BMR in order to determine your daily caloric needs.