Question

Slow-twitch muscle fibers are primarily used for which type of activity?

• A. Sprinting
• B. Endurance
• C. Jumping
• D. Explosive strength

Hint:

Slow-twitch = stamina and endurance, while fast-twitch = speed and power.

Answer 1

The Correct Option is B

Concept: Muscle fibers are classified into slow-twitch (Type I) and fast-twitch (Type II) based on contraction speed and fatigue resistance.
Slow-Twitch Muscle Fibers (Type I):
Contract slowly but sustain activity for long durations.
High resistance to fatigue.
Rich in mitochondria and myoglobin.
Depend on aerobic respiration.
Activities Using Slow-Twitch Fibers:
Long-distance running
Cycling
Swimming (long duration)
Marathon events
These are all endurance-based activities. Why Other Options Are Incorrect:
Sprinting → Fast-twitch fibers
Jumping → Explosive fast-twitch action
Explosive strength → Fast-twitch fibers
\[ \boxed{\text{Answer: (B) Endurance}} \]