It's that question again, of gaining muscle while losing body fat. I'm not a complete noob, so I understand that you need a net surplus of calories to increase LBM. However, I also heard that when performing cardio for more than 20-30 minutes in your target heart rate zone, the body turns to fat for fuel. If your heart rate is too fast, then your body will burn muscle for energy (after using glucose and carbohydrates already floating around in the blood, or something like that). So my question is this, why is not possible then to burn fat and gain muscle at the same time?

by the title you know its been asked before many times why not put(gain muscle while losing fat) into the search engine.

You can gain muscle whilst burning fat. It just most likely wouldnt be optimal gains.

Generally speaking, if you do aerobic cardio for 20-30 minutes you'll be burning both fat and glycogen ( carb based energy ) at the same for most of the cardio session.

As your heart rate increases toward your MHR, the higher intensity just means you burn a greater proportion of of carb based energy - glycogen - that is stored in your muscles.....the higher heart rate is not synonymous with burning muscle for energy ( especially in the context of cardio for 20-30 minutes ).

It is possible.

Just do it the ol' fashioned way, lose the fat in defecit, then build the muscle in surplus. Its tried and true.

yep. its a very slow process to build muscle while reducing fat. its much more straight forward to choose one or the other.

you CAN lose fat and retain muscle
you CAN gain muscle and minimize fat gain


Few people are blessed with the genetics to do both at the same time, with results that don't take months to be seen.