Yo-yo dieting, a phrase coined by obesity experts, refers to a period where weight-loss occurs due to an extreme reduction to calories and a subsequent period when the weight is put back on. Yo-yo dieting is a massive problem, not only does it give the false impression that the diet is going to work initially but it also leads to physiological changes that actually cause an increase in body fat.
In short, the reasons for yo-yo dieting are due to an initial calorie restriction that is too extreme. As previously mentioned, any extreme calorie restriction will results in weight-loss (not fat-loss), almost everyone loses weight initially, but it never takes long for the body to catch up and start preserving its energy. This initial weight-loss is often deemed to be an extremely positive result for the dieter but this is not the case. Over time however the problems associated with such an extreme calorie restriction materialise and make it almost impossible to continue. Ultimately, the dieter will revert to their old eating habits and be in a worse position, both physiologically and mentally, than when they started.
The Psychological Affects: As covered above, after the initial weight loss period the dieter reaches a plateau stage where it becomes increasingly more difficult to lose weight. This lack of results, together with the inevitable gnawing of hunger pangs and cravings is what causes people to give up: very often out of sheer frustration. Once off their diet, the weight starts to pile back on, only now they have less lean muscle than before and a slower metabolism. So the dieter is now feeling a) frustrated that they have quit b) upset that they have not only failed to lose weight but that the weight is now starting to pile on again and c) less motivated to lose weight again. Such an emotional state will often lead to the dieter eating more (for comfort in many cases) and eventually end up repeating this cycle, each time increasing the negative effects of the yo-yo dieting.
The Physiological Affects: As previously mentioned, when you eat less your body will burn less, i.e. your metabolism will slow down. This means that the same calorific intake that used to be affective at maintaining weight will now cause a calorie surplus and actually cause you to put on weight. With each repeated bout of dieting your metabolism becomes less and less efficient until the point is reached where eating less food will actually cause weight-gain. A great book that describes the process of actually gaining fat when you diet, 'Burn The Fat, Feed The Muscle' uses a case study to explain exactly how bad this can be. I have chosen one of my clients as a case study (before he came to me) and explained what can happen below.
The dieter was male, weighed 89kg and had 20% body fat. His goal was to lose 6kg. A pre-examination revealed that 17.8kg of his total mass was body fat and 71.2kg of his total mass was lean.
He started his diet (like most) with and extreme initial calorie deficit and began to lose weight. It didn't take him long to lose the weight and by week 5 he was weighed 82.4kg. So he succeeded... ? It would seem that by weight loss alone he was successful (and if this was his goal then he had been), however upon reexamination it was clear that he was not successful. He now weighed 82.4kg and had 18% body fat. Therefore he had lost a total of 6.6kgs and now had 14.8kg of body fat and 67.6kg of lean mass. This means that 61% off his weight loss came from lean muscle mass. This drop in lean mass had decreased his metabolism and he was now burning fewer calories per day.
Once the diet was over, and the client was happy with his weight-loss and returned to normal eating again. As a result of his now slower metabolism, the number of calories that used to be efficient at maintaining his weight now caused him to gain weight. A few weeks after the end of the diet he was back to his original weight of 89kg, however he now had 23% body fat and 77% lean mass. He was back to the start but with more fat, less muscle and a slower metabolism. This made it increasingly harder to lose body fat each time the dietary pattern 'recycled' itself, and the curse of yo-yo dieting was upon him.
So yo-yo dieting is not just losing the weight and putting it back on, it carries with it severe negative psychological and physiological effects.
Don't worry though, there are ways to burn body fat and keep it that way. My next article will cover some of these methods in more detail.
For more information, pictures, and videos of Functional Fitness Training and how to effectively lose weight please visit Rigs Fitness: http://www.rigsfitness.co.uk. The home of Functional Training in the UK.
Article Source: http://EzineArticles.com/?expert=Sam_Ray_Smith
No comments:
Post a Comment