The fastest muscle in the human body is the eye muscle.
Why it is true
The extraocular muscles can dart the eye back and forth in just milliseconds, allowing us to track fast-moving objects and read quickly.
Source: Anatomy
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This is the reading side of the site, so the answer is in the sentence above — that is the whole point of it. Test yourself works the other way round: the question comes on its own, and the fact and the explanation only appear once you have answered.
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