Written by the Fiveable Content Team • Last updated September 2025
Written by the Fiveable Content Team • Last updated September 2025
Definition
Fast glycolytic (FG) fibers are a type of skeletal muscle fiber that contracts quickly and powerfully, using anaerobic metabolism to generate energy. They fatigue quickly compared to other types of muscle fibers.
Related terms
Skeletal muscle: A type of muscular tissue that is attached to bones and is responsible for voluntary movements in the body.
Anaerobic metabolism: A way cells generate energy through the breakdown of carbohydrates without the use of oxygen, primarily used during intense exercise.
Muscle fatigue: The decline in ability of a muscle to generate force, often experienced after prolonged or intense activity