Refer to the figure showing the leg muscles of two athletes. Investigators studying the leg muscles of Lance Armstrong, formerly recognized as the seven-time winner of the Tour de France bicycle marathon, would likely find _______ muscle fibers, as shown in the panel on the _______.
A) abundant slow-twitch; left
B) hyper-efficient slow-twitch; left
C) atrophied (neglected) slow-twitch; left
D) abundant fast-twitch; right
E) atrophied (neglected) fast-twitch; right

Question

Refer to the figure showing the leg muscles of two athletes.  Investigators studying the leg muscles of Lance Armstrong, formerly recognized as the seven-time winner of the Tour de France bicycle marathon, would likely find _______ muscle fibers, as shown in the panel on the _______.
A) abundant slow-twitch; left 
B) hyper-efficient slow-twitch; left 
C) atrophied (neglected) slow-twitch; left 
D) abundant fast-twitch; right 
E) atrophied (neglected) fast-twitch; right

Quizplus · Accepted Answer

Slow-twitch muscle fibers are specialized for endurance activities and have a high capacity for aerobic respiration. Lance Armstrong's success in endurance events like the Tour de France suggests that he would have a higher proportion of slow-twitch muscle fibers, as shown in the panel on the left.

Refer to the Figure Showing the Leg Muscles of Two