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Sports

Muscle Dynamics in Sports

Quick fact

Your muscles contain a mix of fast-twitch and slow-twitch fibers; elite sprinters may have up to 80% fast-twitch fibers, while marathon runners have over 80% slow-twitch.

Why this is interesting

Ever wonder why a sprinter's legs burn after 100 meters while a marathon runner keeps going for hours? The answer lies in how your muscles dynamically switch between energy systems and fiber types.