Below are EMG traces from bipolar surface electrodes placed…

Below are EMG traces from bipolar surface electrodes placed on four muscles, recorded at once. The trace at the bottom is the force, which shows that the subject increased force almost immediately, and maintained a target level of force production for several minutes. The force trace was recorded by a force-measuring device placed beneath a foot pedal; so, pressing down on the pedal with the foot produced the change in force shown on the bottom. Based on this information, which of the EMG traces below corresponds to the agonist muscle producing the force?    Image description: Labels A-D relate to muscle activation traces relative to a force trace on the bottom.   Reference: Ch. 15

Disregarding what you’d like to study in an experiment, imag…

Disregarding what you’d like to study in an experiment, imagine your subjects are incredibly sensitive and vulnerable. You’d like to measure muscle activity but need to be considerate of the technique implemented to do so. Which technique should you consider using to minimize subject discomfort and risk?   Reference: Ch. 15