Lets think about burning fat, gaining lean mass, and improving fitness. Everyone seems to think they need to do longggg cardio to lose weight. They may walk or get on the elliptical for hours a day thinking they’re doing the right workout to get the best results. Cardio equals losing weight and getting abs right? Unfortunately, No. This eats up a lot of your time when you could get the same results or better in a much shorter workout. Also, being super skinny should never be the goal. I believe this is unrealistic and unhealthy. Weight training by itself and mixed into circuits/intervals is a great way to sculpt the healthiest version of yourself.
Your muscles receive energy and contract because of Adenosine Triphosphate (ATP). This is a large molecule that the body creates through three different generating systems.