Comparison of surface electromyography and myotonometric measurements during voluntary isometric contractions.

Objectives: Muscle stiffness increases during muscle contraction. The purpose of this study was to determine the strength of the correlation between myotonometric measurements of muscle stiffness and surface electromyography (sEMG) measurements during various levels of voluntary isometric contractions of the biceps brachii muscle.

Subjects: Eight subjects (four female; four male), with mean age of 30.