Just read an article about how exercising before breakfast burns
more fat. Article makes it sound like it's new news. Heard this for a long
time. Problem is that people will just read the headlines and then start
running on an empty stomach. It's true that when you run on an empty stomach,
your body will use up any remaining glycogen (carb) stores and then begin to
burning fat. Nothing wrong with that. However, what a runner has to ask
himself/herself is...."What is my goal?"
If your main goal is weight loss, then great idea to get up
early and go for that 3-5 mile run before breakfast and possibly burn more fat
than if you had eaten first. But, if your goal is training for a half or full marathon,
then your main focus should be on achieving a quality run. Running 10-20 miles
on an empty stomach is not going to provide a quality run. When a runner comes to me to talk with me about a recent lackluster run, 90% of the time it boils down to
improper fueling.
Yes, you can burn fat as a fuel source. When all the fat is
gone, you can even burn protein (muscle), which is not good. But the thing to
keep in mind is that the body's main fuel source and most efficient fuel source
is glycogen (what carbs are turned into and stored as in the muscle). Fat can
be an energy source, but it's not as efficient as glycogen.
Sometimes weight loss will happen when half marathon or full
marathon training, but I don't encourage runners in the thinking that running
long is going to cause weight loss. If you are training properly, your appetite
will increase and as long as you're appropriately fueling based on your
activity level, then you'll be fine. Most of the time, however, runners will
over estimate their calorie burn and they'll eat a lot more than they need. My
other concern with this article is there will be people who think.... "I'm
going to run on an empty stomach and then I'm not going to refuel afterward
either. That way I'll really get a good burn." Problem with that thinking
is that when you drastically decrease your caloric intake and drastically
increase your activity level, the brain will go into protective mode and
actually latch on to and protect your body fat and burn muscle instead.
Decreased muscle means less caloric burn, which can mean weight gain or a weight plateau. Not good.
So, long story not so short...if your goal is weight loss,
then try running shorter distances before breakfast as a part of your weight
loss goal, but if you're goal is a marathon....eat.
