Muscle hypertrophy or muscle building involves a hypertrophy or increase in size of skeletal muscle through a growth in size of its component cells. Two factors contribute to hypertrophy: sarcoplasmic hypertrophy, which focuses more on increased muscle glycogen storage; and myofibrillar hypertrophy, which focuses more on increased myofibril size.[1] It is the primary focus of bodybuilding-related activities.
- ^ Baechle TR, Earle RW, eds. (2008). Essentials of strength training and conditioning (3rd ed.). Champaign, IL: Human Kinetics. ISBN 978-0-7360-5803-2.[page needed]