Which skeletal muscle fiber type is characterized by having the largest diameter and the lowest resistance to fatigue?
Show answer and explanation
Correct answer: Type IIb/IIx (Fast Glycolytic)
Type IIb (or IIx in humans) fibers are designed for rapid, powerful contractions. They have a large diameter and rely on anaerobic glycolysis, leading to a quick buildup of lactic acid and rapid fatigue.
Keep practicing
More Muscle Fibers questions
- The 'red' color of certain muscle fibers is primarily attributed to high concentrations of which protein?
- Which organelles are significantly more numerous in Type I muscle fibers compared to Type IIb fibers?
- Type IIa muscle fibers are often referred to as 'intermediate' because they:
- In the human body, where would you most likely find a high proportion of Type I muscle fibers?
- Which of the following is a characteristic of Type IIb (Fast Glycolytic) fibers regarding glycogen content?
- Which fiber type would have the highest density of surrounding blood capillaries?