Posted on 24 Nov 2014

What Type of Twitch are You?

What type of runner are you? Are you a sprinter or a distance runner? The difference could be the type of fibres in your muscles. Muscle bundles are broken up into myocytes; this is then divided into many myofibrils. Myofibrils are strands of proteins that have the action of grabbing and pulling. This action shortens the muscles and the muscle contracts.

The general belief is there are two types of muscle fibres, and they are slow twitch and fast twitch. Whether you are a slow twitch or a fast twitch runner seems to be influenced by how the muscles respond to training and any physical activity undertaken. On average the split between the slow twitch and the fast twitch tends to be 50%, however, there are genetic influences as to how that split in made up.

Slow twitch muscles tend to be more efficient at utilising oxygen for continuous movement, therefore helping athletes to run marathons and long distance bicycle races. Fast twitch muscles use anaerobic action to generate fuel, and therefore create short bursts of speed. Fatigue is more evident in fast twitch muscles; however, a sprinter only needs to generate a great deal of force in the short term.

The difference between the slow twitch and fast twitch runner can also be extended to the volume of blood vessels contained in the muscles. Slow twitch muscles need a rich supply of blood that has been oxygenated to produce energy. As fast twitch muscles use anaerobic action a rich blood supply is not need. The result is fast twitch muscles are lighter in colour than slow twitch muscles.


Health and Fitness Advice by FitFarms Editorial Team

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