Skeletal muscle fibres can be broken down into two main types: slow twitch (Type I) muscle fibres and fast twitch (Type II) muscle fibres.
Fast twitch muscle fibres are the thick muscles responsible for giving the body speed, agility and power. These muscles are engaged by high intensity, anaerobic, short-burst activity.
Slow twitch muscle fibres are the aerobic fibres responsible for fat burning. These narrower muscles sustain activity for a longer time because they are more efficient at burning oxygen. (Think slow burn.)
Muscle fibre composition is genetically determined, but appearance and the way the muscles react can be altered through training. For example:
- Bodybuilders bulk up by focusing on explosive movements that stimulate the fast twitch fibres
- Marathon runners are long and lean because they stimulate the slow twitch fibres through endurance training
Are you more interested in toning and muscle definition than bulking up? Lagree Fitness focuses on slow, controlled, continuous tension to effectively stimulate the slow-twitch fat burning muscle fibres.
