For the third maximal isometric contraction, at 3 seconds into the contraction, two 1 millisecond square wave superimposed stimuli at 100 Hz will be delivered 10 milliseconds apart. 2 seconds after the contraction the same stimulus will be applied. At 7 seconds after, two stimuli will be delivered 100 milliseconds at 10 Hz apart and 12 seconds after a single stimulus will be delivered.