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Name: Dean A.
Status: Educator
Age: 50s
Location: N/A
Country: N/A
Date: August 2004

I understand that, if you regularly consume insufficient calories to meet your basal energy expenditure (BEE), your body will compensate by going into "starvation mode." But what happens when your total calorie intake is above BEE (barely), and you engage in daily exercise of fairly high intensity and duration?

For example: suppose a young man whose BEE is about 1900 kcals regularly eats 2000 kcals/day and expends 800 kcals in exercise, in addition to otherwise light daily activity. Will this result in healthy weight loss, or will his body react as if he is not getting adequate nutrition?

Lets start by making sure we understand the BEE term...

The BEE computed as: Basal energy expenditure: the amount of energy required to maintain the body's normal metabolic activity, i.e. respiration, maintenance of body temperature etc. Male: BEE = 66.67 + 13.75W + 5H - 6.76A

The answer to your question is then if a person could take in about 5% more than what they need to ruin basic body functions and then expend about 40% of that on exercise...My first response is...They will not be able to do it for long. The body needs energy to work muscles in exercise...if it does not get it, it will get into starvation mode. The scenario you present is essentially a very serious caloric deficit of at least about 800 calories and the person's body will be starving for calories. If they have a fair amount of body fat, they will still metabolize some of their muscle mass while losing weight. This would NOT be a healthy situation at all in my opinion.


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