Your metabolic rate affects the amount of energy your body uses at all times. Even when you are inactive, your metabolism is still burning calories, just to keep you alive. Therefore, anything that increases your BMR (basal metabolic rate), such as exercise, will have a tremendous impact on using and thereby reducing your fat levels.
Ironically a diet that is very low in total calories triggers a metabolic response known as the “famine” response. This is a drastic reduction in metabolic rate intended to conserve energy stores and maintain any stored fat that may exist. Although the calorie intake is reduced, the calorie usage by the body is also reduced. Therefore the theory of low calorie dieting as a sole means of reducing body fat is largely ineffective.
This type of dieting leads to become what has become known as the “yo-yo syndrome”. People go on calorie-restricted diets for a period, followed by a return to “normal” eating habits. Weight loss during low calorie diet is approximately 50% muscle and 50% fat (as they are not exercising) and the weight regained during the return to “normal” eating habits is in the form of fat. Not a good result!!
So, if low calorie diets aren’t the answer then what is? Basically, you need to reduce dietary fat intake permanently. Remember that on a per/gram basis, fat is highest in calories and you need to exercise.
The effects of exercise on metabolism extend beyond the duration of your workout. Your basal metabolic rate (BMR) is increased with continued training and this increases your body’s ability to burn fat during recovery/rest days. Remember the burning of fat during the workout is not the key issue; it is the increase in your BMR through exercise that will result in an improvement in your body’s ability to burn fat