Musculoskeletal Final Slides

this protein thread winds around an actin filament

this protein is located at intervals along the filaments

1

2

3

Muscles not used decrease in size. This is called

occurs only if muscle contracts to at least 75% of maximum tension.

Select all that is correct: Slow-twitch fibers

• tend to be aerobic, have more endurance, have many mitochondria and are dark in color from myoglobin

• have low maximum tension that develops slowly, have substantial reserves of glycogen and fat

• examples: long-distance running, biking, jogging

• examples: sprinting, weightlifting

Select all that is correct: Fast-twitch fibers

• tend to be anaerobic, develop maximum strength in a burst, motor unit contain many fibers

• fibers are light in color and have few mitochondria, dependency leads to fatigue

• examples: sprinting, weightlifting, swinging a golf club

• examples: long-distance running, biking, jogging

a condition where bones are weakened due to a decreased bone mass, develops around age 40, can lead to fractures and other complications