Objective 17

Question 0

Explain how the number of muscle fibers stimulated affects the Force of Muscle Contraction

Answer 0

It affects the degree of motor unit recruitment

Question 1

What four things affect the force of Muscle Contraction?

Answer 1

• Number of muscle fibers stimulated
• Relative size (diameter) of the fibers
• Frequency of stimulation
• Degree of muscle stretch

Question 2

Explain how the relative size (diameter) of the muscle fibers affects the Force of Muscle Contraction

Answer 2

The bulkier the muscle, the greater its strength

Question 3

Explain how the frequency of stimulation affects Force of Muscle Contraction

Answer 3

The greater the frequency, the increase in tension

Question 4

Explain how the Degree of Muscle Stretch affects the Force of Muscle Contraction

Answer 4

Muscles contract strongest when muscle fibers at at 80% of their normal resting length or stretched over 100% (to about 120%)