What is the medical term meaning recording of the strength of muscle contractions?

An electromyogram (EMG) is a test that is used to record the electrical activity of muscles. When muscles are active, they produce an electrical current. This current is usually proportional to the level of the muscle activity. An EMG is also referred to as a myogram. The procedure is quite painful as the technician has to stick a needle connected to a meter that reads and conducts electrical current. You have to flex at some points while the needle in in the muscle. It requires at least 20 or so insertions of the needle following the nerve branch. It feels like torture but cannot be done any other way.