The overweight should exercise less to burn more fat

If you’re carrying a few extra pounds – you know that exercising would be hugely helpful.  But the thought of moving your big self around, is intimidating, so sometimes it is easy to just skip it.

But, research published in the British Journal of Sports Medicine, suggests an intensive session of exercise is actually not what you need.  Turns out, less exercise is in fact more.

In search of  Fat Max

The study assessed “fat” burning in a bunch of 12 year old boys.  17 of the boys were obese, the remainder, 12 in total, were lean mean cycling machines.

The boys were strapped onto cycling machines which could ratchet up the level of exertion at regular intervals.  So every 3.5 minutes, the wheels went a little faster – the point of the “exercise” was to ascertain at what point “fat” burning was maximal.

Determining the “Fat Max” is based on calculating the amount of oxygen breathed in, versus the amount of carbon dioxide breathed out per minute  i.e. VO₂ peak.

Fat max lower in fat teens

The VO₂ peak varied between individuals, but there was a clear pattern.  

Skinny boys VO₂ increased steadily, as the intensity of the exercise increased.  It  peaked between 50 – 60 % and then levelled off, remaining within this range.

Fat boys also saw the VO₂ increase, but peak levels were reached at a much lower level of exercise, the peak value was 30 %.  As the level of exercise increased – “fat” burning dropped sharply, so by the time the fat boys were doing intensive exercise, they were running on fumes, not fat.

Of course,  if you’re running on fumes – you’re effectively running on empty, so you’re a hair and a freckle off “death”.  Okay, it is a bit of an exaggeration, but you feel pretty close to death and certainly not in the mood to continue exercising. 

Shoddy muscles not up to the task

The break down in performance, more than likely reflects the state of the muscles.    

The muscle fibres which dominate in obese individuals are “fast twitch” fibres, also known as type 2 fibres.  Fast twitch fibres primarily run on carbohydrate, not fat, so the out of shape muscles can’t mobilize the “fat” to burn it, hitting “the wall”.

The superfit also sometimes “hit the wall”, but this usually happens after prolonged exertion, not a relatively short exercise session in a lab.

The catch twenty two

1. To burn fat, you should exercise.
2. To burn fat when you’re exercising, you need muscle.  But obesity has a tendency to produce BIG wimps, because insulin resistance, the metabolic problem that causes you to pack on the pounds in the first place,  deprives muscles of food.
3. Exercising without muscle is really hard and doesn’t really burn fat.

Eish ! 

Strive to build that muscle

For the uninitiated – exercise is exercise, but for the exercise buff, exercise does different things, depending on the type of exercise.

• Building muscle requires “resistance” training.
• Burning fat requires “aerobic” exercise.

In resistance training you focus on “hurting” the muscle enough to cause the body to respond by patching it up.  This is the exercise you want to focus on if you’re struggling with your weight, because it “builds that much needed muscle”.

Feeling the burn a pipe dream ?

Aerobic exercise requires you to huff and puff and pull finger, so that you burn lots of calories. 

This is the type of exercise the weight loss gurus often punt as a way to tip the weight fomula so that

Energy in < Energy out

But it is a much tougher option and often leads to disappointment for those trying to exploit this strategy to melt away the pounds.  Because in the obese, the body chemistry is wired to store fat, not burn it.

Think muscle not fat

You should exercise, the ideal exercise routine should include both aerobic exercise to get the blood moving so that you charge the heart battery up and resistance training to build muscle. 

When you exercise you might find it beneficial to adjust your expectation.  The small change in perspective will increase the odds that you will stick with the programme and ultimately reap the benefits. 

So when you’re sweating up a storm,  think muscle building rather than fat burning.  Thinking this way means you stop when your muscles have had enough, not when you can’t breathe and your heart feels like it will explode out of your chest.   Remember, by the time you’ve reach this point, you’re probably not burning much fat anyway !

Increase energy out through muscle power

Building muscle is easier than burning fat and more muscle will mean you’re burning more fat even when you’re watching TV. 

Comparison of fat oxidation during exercise in lean and obese pubertal boys: clinical implications. Br J Sports Med (2009) 43:869-870. G Zunquin, D Theunynck, B Sesboüé, P Arhan, D Bouglé

 

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Further reading

To give your baby-2-be a strong heart enrol them in an exercise class	Eating protein saves your muscles while the fat cells burn	Don’t just sit there – hop up every so often and do something

The 7 Big Spoons™…. are master switches that turn health on.

Balance Eicosanoids	Rein in insulin	Dial down stress	Sleep !	Increase Vit D	Culivate microflora	Think champion

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