#5 – What is hypertrophy? Really?
When you lift weights you will increase in size. This process is called hypertrophy. There are two distinct types of hypertrophy: Sacroplasmic Hypertrophy, and Myofibrillar Hypertrophy.
Sarcoplasmic Hypertrophy is that familiar “pump” you get when you curl for the girls, or pump tris for the guys. It is an increase in volume of sarcoplasmic fluid (Semi fluid interfibrillar substance) in the muscle cells. This fluid does not contribute to the production of muscle force.
Myofibrillar Hypertrophy is an increase in the contractile filaments actin and myosin. This means that by increasing these contractile proteins, you increase muscular strength and a small amount in muscular size.
As a generalisation, sarcoplasmic hypertrophy is more prevalent in the muscles of bodybuilders, while myofibrillar hypertrophy is greater in Olympic Weightlifters. (Zatsiorsky & Kraemer, 1995). Genetics and the type of training you participate in will contribute to the type of hypertrophy most prevalent in your body. Have fun!
Zatsiorsky VM, Kraemer WJ (1995). Science and Practice of Strength Training. 2nd Ed, 50., Human Kinetics Publishers