Last week I attempted to reel you in with a catchy title intended to appeal to the deep-seated desire in all of us at this time of year to start losing some serious amounts of recently-gained weight. The trail continues this week with ‘fat-fighters’, perhaps a somewhat aggressive slant on the subject, but let’s face it, what is this if not a war?
We want to annihilate an enemy quickly and efficiently, and all good military strategists know that information can spell the difference between victory and despair. Indeed, as quoted in Sun Tzu’s ancient text, Art of War, you must “know thy enemy”. If we’re going to wage war on fat, we must understand it. So let’s delve a little deeper, or just beneath the skin to be precise.
Most of the fat we target is stored just beneath the skin, or ‘sub-cutaneously’. It comes from the food we eat, because food is, simply put, energy. We eat food as fuel, to support our essential life-sustaining functions and any physical activity we perform throughout the day.
If you’re exercising at at least 70 per cent of your maximum heart rate, you’re working hard enough to stimulate the release of hormones responsible for breaking up stored fat
Throughout our evolutionary history the body has assumed the marvellous ability to store this food away for a rainy day. You might be able to gorge on food after a successful hunt, but who’s to say tomorrow’s hunt will yield the same spoils? You might face a day or more of starvation. Energy that isn’t immediately required therefore can be stored away as fat, so it can be mobilised later on whenever it is needed.
When the macronutrients (proteins, carbohydrates and fats) enter the bloodstream after digestion, they are taken away to perform all the specific jobs they were designed for. Anything not immediately required by the body however, is processed by the liver and turned into fat. Fat that was ingested originally as ready-formed fat is simply reconstituted at this point. All this new fat can now be stored in fat storage cells situated around the body in our traditional ‘problem areas’.
All very interesting you might say, but how do we get rid of it? There is an incredibly wide range of methods and techniques at our disposal for mobilising and using this stored body fat, anywhere from jumping up and down in a studio to heaving chunks of metal around in a gym. The methods you choose are better determined by other variables, such as personal preference or physical requirements rather than their supposed effectiveness or superiority over another, which is very difficult to prove comprehensively anyway.
If you’re carrying a significant amount of extra weight, for example, then you might prefer an impact-free system like cycling instead of walking or jogging. If you are naturally interested in a specific type of training then you’re more likely to maintain the motivation required to put in the necessary work without giving up. Whatever you go for, the cardinal rule is that you must reach a certain level of exercise intensity if you want your efforts to yield meaningful results.
Research generally supports the 70 per cent rule. If you are exercising at at least 70 per cent of your maximum heart rate, then you know you’re working hard enough to stimulate the release of the relevant hormones responsible for instigating the breaking-up process of stored fat. This would mean working hard enough to just about be able to hold a conversation with someone. If you can’t talk at all, you’re unnecessarily high above the mark, but if you can sing, you’re taking it too easy.
Some of this released fat is used up straight away by the muscles that need it, while the rest of it needs to pass through a sequence of additional chemical processes before it can also be used. This means that fat is actually a highly dense form of lasting energy.
A popular misconception is that we have to ‘burn’ up all readily available forms of energy such as sugar and glycogen in the bloodstream, muscles and liver before we can start mobilising stored fat. The question therefore often tends to be: “How long into a workout before I start burning fat?”
Well, remember that when it comes to triggering the process it is a question of intensity rather than duration, so just ensure you warm-up effectively, and get along with achieving your planned goals for the session however long it may be. Fat will be burned alongside more readily available fuels, and not exclusively, so all we need to worry about is that we are working hard enough and accumulating enough of the exercise overall.
And finally, if you’ve ever wondered where the fat actually ends up, a recent edition of the British Medical Journal has revealed a fascinating answer. A team of Australian researchers from the University of New South Wales have been busy investigating the precise biochemistry of weight loss.
They found that while many health professionals were under the impression that fat is converted to pure energy or heat, it actually ends up, literally, in thin air. It is breathed out of the lungs, as carbon dioxide. By following the atoms in fat through the entire process of weight loss they found that out of every 10 kilograms of fat, just over eight is exhaled, while the remainder becomes water to be excreted by the body via a range of means.
So now that you know a little more about thy enemy, what will your next move be?
matthew.muscat.inglott@mcast.edu.mt