subject holding out an extended arm and the tester pressing down on the wrist of the extended arm, using two fingers and light pressure. Usually the subject holds a substance to be tested over their solar plexus with the other hand. The tester says to the test subject, “Resist,” and if the substance being tested is beneficial to the subject, the arm will be strong. If it is not beneficial or it has an adverse effect, the arm will go weak. The response is very quick and brief.
