My contribution has to do with calories:
Calories are a measure of energy
Calories = Total energy
Total energy = potential energy + kinetic energy
Calories = potential energy + kinetic energy
Kinetic energy = energy used through body metabolism and exercise
Potential energy = energy stored (body fat)
Therefore:
Calories = body fat + metabolism + exercise
If one wants to decrease body fat, while keeping calories constant, calories used from exercise and metabolism must increase. We have limited control over calorie usage from metabolism, while we have total control over how much we exercise.
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