Can You Burn Fat Whilst LIfting Weights?

There is not a day that goes by that a client or a member of my training center asks me; "Can I burn fat lifting weights?" I wish the answer was a simple yes or no, but it really isn't. Instead of giving them my thesis paper all over again, I thought I'd write it here.

First and foremost, let me state that the body has three energy systems constantly working albeit in different ratios and proportions based upon the intensity of the exercise and the duration of said exercise. The three systems are ATP-CP system (the energy that exists right in the cell), the Anaerobic Glycolytic System (breaking down carbs for energy), and the Beta Oxidation system (Fat Metabolism.)

ATP -CP System this system is used primarily for quick energy. It is energy that resides and exists right in the mitochondria (the power house of the cell.) This is high intensity and fast acting, however it is very limited for its duration 0-30 seconds best for this one. Great out of the gate, but no staying power.

Anaerobic glycolytic System- this system breaks down carbs into energy by a multiple step process that enables the body to enter into the Krebs cycle or the Corey cycle. Depending upon whether there is oxygen or enough oxygen present during the exercise. This is the system along with the ATP-CP system that is primarily used during resistance training. The body uses carbs and the storage form (glycogen) to produce energy while lifting weights. It is quick hitting, quick acting and is able to be used without the presence of oxygen. Remember resistance training is anaerobic in nature (meaning it is without oxygen.)

Beta oxidation system- this is the system that breaks down triglycerides to produce energy. This system is for activities of a continuous rhythmic nature and this system does not kick in significantly until 16 minutes or greater. The triglycerides must have two things present in order to be chemically cleaved so they can be used for energy. Those two things are water and oxygen. First the fat molecule must be hydrolyzed, and then it must be oxidized. Let me give you an easier to understand illustration: If you were going to start a fire in a fireplace you wouldn't just hold a match under a log and expect it to catch fire. You need kindling under that (maybe some newspaper or some wood chips) as the match hits the kindling it catches fire then ultimately the kindling catches the logs on fire. Same thing with fat metabolism - the oxygen is the kindling. If you have no oxygen you can't break down the fat molecules.

Now, indirectly you do burn fat with resistance training due to the fact that the more increased muscle you have, the more calories you burn even at rest. However, during the resistance training session itself, you use almost exclusively, carbohydrates as energy to perform the exercises. So in the end, in order to most effectively change your body into the body of your dreams (or your girl's dreams) you should allow resistance training to play the role that it is meant to do. Deplete muscle glycogen stores and break down the contractile proteins in the muscle so they must rebuild stronger and more dense, and allow cardio to play its role, that of a fat burner. Cardio will used stored energy (fat) as energy and thus changing your body composition.