fast-twitch

adjective

ˈfas(t)-ˌtwich How to pronounce fast-twitch (audio)
: of, relating to, or being muscle fiber that contracts quickly especially during brief high-intensity physical activity requiring strength compare slow-twitch

Examples of fast-twitch in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
The engines of performance — max heart rate, muscle mass and fast-twitch fibers among them — wane. — Matthew Futterman, New York Times, 6 Sep. 2026 Maintaining muscle mass—particularly the fast-twitch kind, which gives us power—is crucial. — Hannah Coates, Vogue, 3 Aug. 2026 Males typically have a greater proportion of fast-twitch muscle fibers, improving explosive speed and power. — Jon Root Outkick, FOXNews.com, 2 Aug. 2026 In soccer, speed is more than just a fast-twitch sprint reflex. — Sally Jenkins, The Atlantic, 18 July 2026 See All Example Sentences for fast-twitch

Word History

First Known Use

1958, in the meaning defined above

Time Traveler
The first known use of fast-twitch was in 1958

Rhymes for fast-twitch

See All Rhymes for fast-twitch

Browse Nearby Words

fast track
fast-twitch
fastuous
See all Nearby Words

Cite this Entry

“Fast-twitch.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/fast-twitch. Accessed 7 Sep. 2026.

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Medical Definition

fast-twitch

adjective
ˌfas(t)-ˌtwich How to pronounce fast-twitch (audio)
: of, relating to, or being muscle fiber that contracts quickly especially during brief high-intensity physical activity requiring strength compare slow-twitch
Last Updated: - Updated example sentences
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