the average person intakes upwards of 1800 calories a day. the military diet only allows you to intake around 900 calories each day for three days. Because of this massive drop in calorie intake the average person is able to lose up to 10 lbs in just 3 days, from diet alone.
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A workout diet plan
Just like starving yourself isn't that easy, Burning 900 calories at the gym isn't that easy. This is why every personal trainer has a diet plan. Just reducing your calorie intake by 400 you will only need to burn 500 calories in the gym allowing you to eat more of the foods you like and not having to be hungry all day.
A good rule of thumb is to burn 500 calories two or three times a week in the gym and reduce your calorie intake at home. Once you've got a grip on your meal plan at home you wont need to be at the gym as much.
Another rule of thumb, count the calories you take-in and then burn that many calories at the gym. just being awake and moving around burns an amount of calories so you would then lose weight quiet quickly. maybe a 1 or 2 pounds every three or four days.