fatigue (muscles involved with such activities as walking and sprinting) c. fast glycolytic fibers (1) largest in diameter (2) can generate the most powerful contractions due to having the greatest number of myofibrils (3) low myoglobin content (appears white in color) (4) relatively few capillaries and few mitochondria (5) can hydrolyze ATP at a rapid rate (6) fatigue quickly (used for activitie