Intense exercise that results in a great deal of anaerobic activity

A) converts some slow-twitch fibers into fast-twitch fibers.
B) increases muscular strength and mass.
C) enlarges slow-twitch fibers.
D) decreases the efficiency of fast-twitch fibers.
E) decreases muscle strength and mass.

Anaerobic Activity

Physical activity that occurs in the absence of enough oxygen for the complete burning of sugars, resulting in lactic acid production.

Slow-twitch Fibers

Muscle fibers characterized by their ability to sustain long endurance activities; they fatigue slower compared to fast-twitch fibers and are rich in mitochondria.

Muscular Strength

The maximal force that a muscle or group of muscles can exert against resistance in a single effort.