Physical Activity Burns Sugar More Than Fat

March 18, 2011

You hear and read a lot about how good it is for diabetics to be physically active because it helps regulate blood sugar. And it does.

So, why then do so many fitness experts procliam that physical activity is good for losing body fat? Well, they think that when you run or play tennis or engage in some form of rigorous physical activity most of the energy being utilized comes from fat stores.

It doesn't. It comes from glucose converted by your body from stored glycogen. And we don't have a lot of it. When marathon runners "hit the wall" around mile 16-20 depending on the individual, glycogen is depleted.

This is why physical activity is so important for diabetics, especially those who do not adhere to a low sugar/carb diet.

So the next time you hear the Jillian Michaels of the world screaming at you that you need physical activity to lose fat, don't you believe it.

Truth is, you'd have to burn through all of your glycogen stores to be bereft of glucose before much if any stored fat comes into play for fuel. I once calculated that you'd have to run at full tilt from NYC to Hartford Connecticut in order to burn one pound of body fat. I could be wrong give or take a small town or two in between, but you get the idea.

Think about that the next time you decide to plod on the treadmill for 45 minutes.