Final answer:
Muscular endurance is the ability to maintain forceful muscle contractions over a long period without getting tired. Activities performed by cheerleaders and ballet dancers are examples of such endurance, often associated with a higher ratio of slow-twitch muscle fibers.
Step-by-step explanation:
The ability to exert force over a long period without fatigue is known as muscular endurance. Cheerleaders and ballet dancers often display this type of strength as they perform activities that require continuous contractions of their muscles. Exercises that improve muscular endurance are beneficial because they make the muscles more resistant to fatigue. This is often due to a higher proportion of slow-twitch muscle fibers, which are especially good at sustaining aerobic activities and are characterized by having more capillaries, mitochondria, and myoglobin. These muscle fibers can carry more oxygen and thus support longer periods of contraction without tiring, which is why endurance athletes, such as marathon runners, typically have a higher ratio of slow-twitch fibers.
On the other hand, resistance exercises, like weightlifting, require fast glycolytic (FG) fibers for short, powerful movements and do not typically target muscular endurance. FG fibers primarily use anaerobic glycolysis for energy, leading to powerful but quick contractions. Therefore, they contribute to muscular strength rather than endurance.