If you're a couch potato, you might feel tempted to try one of those 'lose weight without exercising' diets. Sometimes they promote use of a product like a meal replacement shake; sometimes the diet involves restricted food choices. They seem to be an ideal choice if you find it hard to haul yourself off the couch and into the gym; but why don't they work in the long run?
WHY DIETING WITHOUT EXERCISE SEEMS TO WORK (AT FIRST)
When your body detects that your food intake hasn't been sufficient to meet your energy expenditure, it has to make up the difference from your energy stores. If you're not exercising regularly your body will tend to eat into your muscle tissue for energy. After all, your muscles aren't being used anywhere near their full potential. Because muscle tissue is so dense and heavy, weight seems to be falling off fast at least that's what the scales say.
WHY YOUR WEIGHT WILL TEND TO PILE BACK ON
Alas, this kind of diet is setting you up for weight gain in the long run. Muscle tissue uses up energy just being there; and when you're exercising it uses up even more. The more muscle tissue you have, the faster your metabolism runs. When your body eats into muscle tissue to supply your energy, you're left with less muscle after a few weeks and an even slower metabolism.
When you return to 'normal' eating your metabolism is now running even slower than before, so its more likely that the weight will pile back on and then a bit more too. It can be very disheartening. Not only that, but because your fat tissue is still there, you will still have that 'blobby' appearance that you wanted to re-shape.
WHY EXERCISE WILL GET YOU THE RESULTS YOU REALLY WANT
If you're exercising regularly however your body will tend to make energy withdrawals from your fat deposits, because clearly your muscles are still being used. One kilo of fat takes up a lot more space than denser muscle tissue, so people who lose weight with exercise lose size first, then weight. They can buy smaller clothes and use a smaller notch on their belt even though the scales say they haven't lost much weight.
But it gets even better. Your regular exercise has increased the proportion of muscle to your fat stores, so now your metabolism runs faster than before. When you reach your weight loss goal, you find that you can eat more than you expected, and maintain your weight loss. Your increased muscle tone will give you a really sexy shape too!
If you want to be able to eat whatever you like, the most effective approach is actually to increase your fitness routine before you make any changes to your diet. Supervised training with a personal trainer is the most effective. You'll find your weight and size reducing, and even better, your cravings for all those 'naughty' foods are diminishing. Now get some professional advice to determine what needs to change in your diet, and you're well on your way to a shapelier you.
Enjoy shopping for all those new clothes in smaller sizes!