pick any body part and record what is the frequency of your

pick any body part and record what is the frequency of your fastest movement in Hz (cycles/s)

(leg, finger, arm, etc)

Solution

According to the given question, I would choose the movement of my fingers. The number of times finger is tapped as fast as possible per second is the frequency of its fastest movement.

The finger tapping motion can be carried out for a minute, and the number of times the finger is tapped can be divided by 60, to determine the frequency. In my situation, the finger tapped 7 times per second. Therefore the frequency of the fastest movement of my finger is 7 Hz.