A weightlifter uses muscles so the muscles exert more than 75% of their maximum tension,this stimulates
A)an increase in slow,fatigable white fibers.
B)muscle fibers developing new filaments of actin and myosin.
C)shrinking of skeletal muscle.
D)conversion of skeletal to smooth muscle.

Question

Quizplus · Accepted Answer

When a weightlifter uses muscles so that they exert more than 75% of their maximum tension, the muscle fibers undergo microdamage. To repair this microdamage, muscle fibers synthesize new filaments of actin and myosin, which ultimately leads to muscle growth and increased strength. This process is known as hypertrophy, and is the reason why weightlifting is such an effective way to build muscle mass. Choice A is incorrect because an increase in slow, fatigable white fibers is not a desirable adaptation for a weightlifter. Choice C is incorrect because shrinking of skeletal muscle (known as atrophy) would result from disuse, not from intense weightlifting. Choice D is also incorrect because it is not possible for skeletal muscle to convert to smooth muscle.

A Weightlifter Uses Muscles So the Muscles Exert More Than