muscle fiber types (fast-twitch, slow-twitch)

Muscle fibers are specialized cells in our muscles that facilitate movement. There are two main types: slow-twitch and fast-twitch. Slow-twitch fibers are endurance-oriented; they contract more slowly, use oxygen efficiently, and support activities like long-distance running or sustained postures. Fast-twitch fibers contract quickly and forcefully but fatigue faster, making them ideal for short, intense movements such as sprinting or lifting heavy weights. Most muscles contain a mix of both types, allowing a balance of endurance and power depending on activity demands.