Fortunately, we don't need to be scientists to figure out how to get fit. But still, it is helpful to understand what makes muscles grow. Basically, a muscle has to be broken down first for it to be repaired and made bigger and stronger. This is what happens during weight training programs. When you lift weights, your muscles suffer a good kind of injury, which leads to the creation new muscle protein - myofibrils. When it comes to muscle or strength training, such process has to be utilized. The important thing is to create a training plan that will give stimulus to the muscles. If you are wondering what is weight training would best benefit your muscles, well, it is one that subjects the muscles to metabolic stress, tension, and muscle damage.