Muscle response to changes in stimulus strength

What is recruitment?

Aka multiple motor unit summation; itcontrols the force of contraction more precisely

What are subthreshold stimuli?

stimuli that produce no observable contractions

What is the stimulus that produces the first observable contraction

Threshold stimulus

That is the maximal stimulus

The strongest stimulus that increases contractile forces. All muscle motor units are recruited.

How is the rectruitment process dictated

By the size principle

What does the size principle say about the motor units of small muscles

The motor units of the smallest muscles fibers are activated first because they are controlled by the smallest, most highly excitable motor neurons.

What does the size principle say about larger muscles

As motor units with larger and larger muscle fibers begin to get excited, contractile strength increases

What does the size principle say about the motor units of large muscles

They are only activated when the most powerful contraction is necessary

Why is the size principle important

allows increases in force during weak contractions to occur in small steps

Are motor units more commonly activated synchronously or asynchonously

Asynchronously

What does the asynchronous contraction of muscle allow for

It helps to prolong a strong contraction by preventing or delaying fatigue.