Question

Usain Bolt, a world champion sprinter, can run a 10-meter split in 0.82 seconds. Say you obtain a quadriceps muscle sample from Usain Bolt and compare it to one from a 25-year-old male long-distance runner. What differences do you expect to observe between those two muscle samples? Select all that apply.

A) red and white muscle fibers of larger cross-sectional area in Usain Bolt's leg muscles

B) more mitochondria in Usain Bolt's leg muscles

C) more fast-twitch fibers in Usain Bolt's leg muscles

Answer 1

The correct answer is are option B and C -  more mitochondria in Bolt's leg muscles and  more fast-twitch fibers in Bolt's leg muscles

Explanation: More mitochondrial is necessary for rapid production of energy during running time, Fast running requires huge amount of energy in a very short tie and for this reason numerous mitochondria is found in muscles of fast runners. Fat twitch muscles are required for quick action as they tired out in long run. As Bolt's duration needed t complete running is less than 1 sec, fast twitch muscles will be very much useful for him as these muscles contract anaerobically ad produce lactic acid. This type of muscle is suitable for sprinting, jumping where instant energy is required. Red muscle fibre is composed of slow twitch muscle and require who are long distance runner. White muscle fibres have few mitochondria , Myoglobin, capillaries. So a sprinter like Bolt will not have much red and white muscle fibre in his legs.