fast-twitchadjective
uk/ˈfɑːstˌtwɪtʃ//ˈfæstˌtwɪtʃ/specializedused to describe a type of muscle that is used for sudden, fast movements such as sprinting (= running fast over short distances):
Fast-twitch fibers use no oxygen and provide quick bursts of energy. Slow-twitch fibers draw oxygen from blood and provide steady, consistent movement.
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slow-twitch