Exercise Enhances Fat Loss and Preserves Muscle

In a comparison of weight loss methods, both exercise and diet groups achieved similar weight loss, approximately 15 pounds. However, the exercise group not only lost slightly more fat (about 3 pounds) but also gained some muscle mass, despite it possibly being water weight. Studies indicate that calorie restriction alone often leads to significant lean mass losses (20-30%), whereas incorporating exercise mitigates these losses by about half. Further analysis reveals that the reduction in daily energy expenditure is directly related to changes in body mass, with lean mass loss contributing more significantly. Moreover, lower body mass decreases the energy cost of movement, complicating predictions of activity-related energy expenditure changes during weight loss.