Weight-loss: You cant out exercise a bad diet...

I spoke with a Krav Maga student some time in 2010. He was not happy. He had been training 2 months and had lost no weight, in fact he had gained weight.

My first question was his diet, and unsurprisingly his diet was not great. It seemed to comprise largely of  microwave meals and take aways. Oh and a fair amount of cider. More to the point he had taken to getting a take away and a tin of coke on the way home from krav maga training. I estimated that this 'curry and chips' diet  would have had at least 1000 ckal and he was doing this twice a week.  Due to his weight and fitness level he was unable to participate in the warm up or conditioning sessions. Sadly he would not accept that he the food was the problem as the Krav Maga had made him hungry.  Shortly after our converstaion he stopped training.

I often struggle trying to explain that it's your diet that controls your weight, not your exercise regime. I try to disabuse people of the notion that the latest exercise program, gadget or machine will cure their weight problem.  I can understand the issue. Its much nicer to buy a new shiny gadget, an exciting dvd collection or join a gym than to miss out on high calorie tasty snacks and food.

The fitness industry compounds this problem. We are bombarded with images of homed lean individuals doing an exercise on some kit or the other, The message is simple and unequivocal. 'Do this and look like me. Join the gym now...'

The fitness industry markets weight loss and the body beautiful heavily. They sell gym memberships like snake oil with a wide range of classes which imply a lean healthy body is built in their classes.  That's why we have thighs, tums and bums, weight loss work outs or fat burning. These classes imply that weight is lost in the class or gym - not off the dinner plate. This simply is not true.

Now exercise is great for you in  a variety of ways but its not an efficient stand alone weight loss tool. Exercise is healthy, its beneficial and will make you look and feel better. Hell it even makes you sleep better, better natured and better in bed ! But the truth is you cant out exercise a bad diet. Weight loss is pretty much dominated by what you put in your mouth. Yes you can add more muscle, yes it does burn more calories but the main and overwhelmingly dominant factor in weight loss is diet.

So with this in mind lets compare activity against diet and see what happens.

The Big Mac rule

I try to explain the issue by using the popular 'Big Mac' as a guide. I am not knocking the 'Big Mac'. It could be any popular fast food, donut or burger. I like the big mac as it contains around 540 calories when eaten without frys or drink. This makes the maths easy.

The amount of calories we require is dependant on our size, gender, physical activity level and body composition. To keep this simple we will use 'average' calories for a man at 2000 kcal and 1500 kcal for a woman, This wont be far off.

How does a Big Mac compare to a formal exercise session ?

We had to make some assumptions, based on a typical adult starting Krav Maga. We assume they are male with an average weight/height of 5'10 and 12.5 stone.    How would a typical 60 minute exercise session compare to this one burger?

1 x Big Mac - No Frys or drink = 540ckal

• Aerobics - low impact 429 ckal
• Krav Maga 689 ckal
• Rowing moderate 300 ckal
• Walking moderate 429 ckal
  

Weightlifting moderate - machines 257 ckal

Swimming general 600 ckal

To be clear, these are approximated averages using an online calculator and whilst the actual figures are heavily dependant on intensity and individual size, they do give a good guide.  Now if you were to consume more than just the big mac, say frys and a diet coke - its around 930 ckal !!!.

So in short, You can burn a Big Mac off with a 60 minute vigorous work out. The problem is that most people consuming this diet are not fit enough to exercise for 60 minutes. Typically they don't exercise at all. If they do typically they  can only train at a low intensity and for less than 30 minutes. Added to this they typically demonstrate unhealthy life style choices. In other words they are more likely to consume the full meal not just the burger.

In short we over consume calories and it requires an awful lot of effort to bur this excess off. In short we cant out exercise our diet.

In conclusion

Exercise is hugely beneficial for you. Attending classes or a gym can supplement a weight loss program, make you stronger, healthier and fitter. But it wont necessarily make you slimmer. For that you need a healthy, balanced and above all calorie controlled diet. More coming on this next week.

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