Let's take a look at these (and other) important players: Closely related to insulin and highly anabolic, IGF-1 is a key regulator of muscle growth.
In fact, it's been suggested that it contributes to muscle hypertrophy by stimulating the proliferation of satellite cells.
Needless to say, sufficient levels of cardio and resistance training don't hurt either.
After all, lifting does more than build boulder shoulders and barnyard back—it induces tissue vascularity, which aids in the circulation of nutrients and oxygen as well as the removal of waste products.
Within hours of muscle injury, neutrophils and macrophages—white blood cells critical to decreasing inflammation—infiltrate your injured muscle.
Small, cell-signaling proteins called cytokines are then released, attracting more white blood cells along with satellite cells.
Over the two-week period in which satellite cells are called upon to heal damaged muscles, our injured fibers are flooded with a residual pool of normally dormant satellite cells.
You push yourself and tear down muscle fibers, so why does the continual stress make you stronger?If you want to build muscle, you have to hit the weights, hard.In order to optimize satellite cell activation and myogenesis—better known as the formation of muscular tissue—you have to maximize the microtrauma that signals muscle injury.On average, a trip through the cell cycle takes 16 hours.Signaling pathways ultimately control the activation and expansion of satellite cells, and enable them to produce larger, stronger muscles.