d. In the experiments, you also varied the frequency of stimulation. What is the

11.. These questions involve an experiment we did in lab. There was no real data to record, more just to see the effects various stimulations, voltages, and varying the frequencies has on a muscle.
a) Explain what happened to active force as the "voltage" increased? As it decreased?
b) Explain what happened to active force at the "rate of stimulation" increased? As it decreased?
c) You increased/decreased voltage in the experiment. In the human body what is equivalent to "voltage"? How does it vary during muscle contraction?
d) You also varied the frequency of stimulation. What is the human body equivalent to that "rate of stimulation"? How does it vary during muscle contraction?
e) Putting it all together, what two things does the human body adjust to maintain a smooth contraction as the weight it bears varies?

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11a. It would make sense that when a motor unit reaches it stimulation threshold (i believe this is around 75mV) it will fire. So when a voltmeter stimulates a motor unit above that threshold, it will fire.

11b. The active force of the overall muscle will increase and decrease as rate of stimulation increases. However, the motor unit individually will remain the same.

11c. The voltage would be analagous to the neural stimulations sent along the motor neurons. Every signal sent done the efferent nerve would be equivalent to the increase in voltage.

11e) The human body will either increase the rate of stimulation to cause the motor units to fire faster to generate more force or it will send stronger signals to increase total recruitment of a muscle group.