Many people speculate about the process of muscle growth, and how one can achieve muscle development. Muscle growth, or as many scientists call it, muscle hypertrophy, is an increase in the size of muscle cells. But first let’s start with the basics. Muscle growth requires three features: a stimulus (exercise), fuel, and repair.
The first step is placing a stimulus upon your muscles, inducing your muscles to work harder than what they are accustomed to. This not only drains energy, but also causes microscopic damage to the muscle fibers. Therefore, your muscles are in need of replenishment. It is then after the workout where you replenish your fuel tank (protein shake) so the muscles can repair themselves. If the stimulus was of sufficient intensity, the muscles will adapt and grow during the repair process.
An increase in muscle size is due to hypertrophic adaptation. Exercise induced hypertrophy affects your red Type II fast twitch fibers (strength) more than it affects your white type I muscle fibers. As the muscle gets bigger it will become stronger as well.