You’ve seen the ads – they are all over the internet, claiming to reduce fat in specific areas if you perform a particular exercise. “Reduce arm flab in 7 days by doing this exercise for 10 minutes a day!” the ads cry! Before you rush off and try it, let me set the record straight that nothing, in fact, could be further from the truth. However I see many people sadly still falling for this.
Don’t get me wrong – increasing exercise when you have a tendency towards being sedentary is always an improvement – it just won’t reap these particular benefits. Why? Because biology and fat loss just doesn’t work that way (if only it was that easy!!).
Fat is stored around the body as subcutaneous fat (adipose tissue) and we are all individually pre-disposed to storing it in particular areas unique to us; some may find their belly fat increases whilst others may store it in hips and thighs or upper body. Increased belly fat can also be an indicator of a more serious fat accumulation – visceral fat – which is stored internally around the organs and can lead to serious conditions such as non-alcoholic fatty liver disease (NAFLD) and contribute towards the onset of chronic diseases such as Type II Diabetes.
When we release fat stores to burn as energy, it is released from all over the body, rather than from the specific area we are exercising. Whilst we can certainly focus on strengthening specific muscles, this doesn’t mean that the fat deposits in that exact area are being used up during the exercise itself.
Losing fat is intrinsically tied to nutrition. I’m sure you have heard of the saying “you can’t out-exercise a bad diet” – and this is true. You won’t achieve your fat loss goals by doing hours of exercise – particularly if you are not tackling any dietary issues you may have which are contributing to the fat gain in the first place.
Releasing fat from your body’s stores to be burned for energy means putting your body in the correct hormonal state to do so. When we think of blood sugar we may tend to just associate dietary sugar with it, but when we eat carbohydrates they are changed into glucose (sugar) in the body and enter into the bloodstream in exactly the same way as sugar. We should only have approximately 5ml of glucose throughout our whole body at any one time and so the pancreas releases insulin to remove the glucose and deposit it around the body as needed; to the cells for energy; the liver and muscles as glycogen (the storage form of glucose which can then be reconverted back into glucose when the cells have used up their supply); and to the adipose tissues as fat. And if we are then compounding this by eating an excess of fructose (either in the form of “healthy fruit” or in processed sweetened foods) we will store even more fat – particularly around the liver – as the fructose won’t be used as an energy source whilst there is glucose to be utilised first. Fructose is metabolised differently to glucose because it is sent directly to the liver, whereupon it may then be delivered to cells for energy – only this isn’t possible if the cells are already full with glucose. So it gets stored as fat instead.
The problems occur when we continually fuel our bodies with carbohydrates (and sugar) throughout the day because this results in fairly constant levels of insulin in the body, as it performs its job of removing glucose from the bloodstream. Insulin is the hormone that encourages our body to store rather than release fat. However, if carbohydrate levels are low, for example when eating a low carbohydrate diet, or practising intermittent fasting, insulin levels decrease and it is when these levels are low that other hormones come into play, such as glucagon and human growth hormone. Glucagon works in opposition to insulin and sends a message to our liver that we need to release fat for energy because we do not have any glucose or glycogen left. Human growth hormone aids in the repair of tissues, helps build muscle tissue and also helps to increase our metabolic rate, providing us with more energy and also assisting in fat utilisation and therefore weight (fat) loss.
However, our bodies have to burn any glucose and glycogen before they can access stored body fat for energy, so the likelihood is that if your diet contains a certain amount of carbohydrates you will be burning sugar not fat during your exercise, let alone losing fat in any specifically targeted area!
Although it has now been established that adipose tissue is active (with brown fat being more metabolically active than white fat), exercise can help us to build lean muscle tissue, which is more metabolically active than adipose (fat) tissue, helping to increase your overall metabolic rate to a significantly higher level. High intensity exercise (HIIIT) has been linked to a reduction in visceral fat levels, but again this will only occur in the absence of glucose, once fat has actually been liberated for energy. And whilst some areas of the body do tend to lose fat quicker than others, this appears to be highly individual and is not something that we can actually “target” specifically.
So, to sum up, although you certainly can increase strength and build stronger muscle tissue via dedicated exercises, you are only going to actually “see” those muscles once you have lost the overall body fat!
Next time you see those internet ads, take a look at what you are doing in the kitchen rather than the gym!