Biology
Muscle Fiber Types
Quick fact
Muscle fibers come in three main types: slow-twitch (Type I), fast-twitch oxidative (Type IIa), and fast-twitch glycolytic (Type IIx).
Why this is interesting
Did you know that your muscles aren't all the same? Some are built for long, steady effort, while others power explosive movements—like a sprint or a weight lift. What makes them so different?