Why is it important to exercise whilst on a weight loss regime?
Well, studies have shown that body composition is different in those who just diet, those who just exercise and those who do both. Those who just diet tend to lose fat-free weight, ie. muscle mass, whilst those who exercise or exercise and diet increase their fat-free weight, losing significantly more body fat. Exercise protects lean tissue, even when dieting.
Protecting lean tissue is as important as losing pounds. Muscle mass determines 80% of the metabolism, so protecting or increasing muscle mass raises your metabolic rate, which in turn burns more calories. Even when your body is just resting, every pound of muscle burns 40-50 calories per day.
On the other hand, a pound of fat burns just 2 calories per day. In fact, if you do not exercise whilst dieting, your body tends to burn lean tissue as much as fat, and you may lose muscle mass, slowing down your metabolism and causing your body to burn fewer calories and store more of them as fat! Women have to work harder to lose weight than men, as their body composition typically has a lower muscle mass and burns an average of 600 fewer calories per day than men's.
Can I exercise more to burn off the calories of the foods I eat, without worrying too much about the foods I consume?
In theory, yes. But you do need to eat a balance of foods and lots of fibre for a healthy body. One study proposes that fibre may help block absorption of the calories provided by fat and protein, and you won't retain as many waste products in your system, so will feel healthier too.
