Final answer:
Fast-twitch muscle fibers fatigue sooner than slow-twitch fibers.
Step-by-step explanation:
Fast-twitch muscle fibers fatigue sooner than slow-twitch fibers. Fast-twitch fibers contain fewer capillaries and mitochondria and less myoglobin, making them better suited for short, anaerobic bursts of activity. On the other hand, slow-twitch fibers are rich in mitochondria and myoglobin, allowing them to sustain aerobic activity for longer periods of time.