Understanding sEMG

For example, nearly 60% of the studies reviewed by Zaichkowsky and Fuchs (1988) that ex- amined the effect of EMG biofeedback reported positive effects on performance. However,thereviewsof Petruzzello,Landers,and Salazar(1991)andCollins(1995

Measurement of the electrical activity preceding muscle contraction is called elec- tromyography or EMG. EMG measures (in microvolts) the electrical energy dis- charged by the motor nerve endings signaling a muscle to contract.

Muscle feedback. An electrornyograph (EMG) is used to detect and measure muscle activity. Once detected, the electrical activity of the target muscle, or muscles, is displayed (fed back) to the individual. The individual then tries to modify the EMG signal in the appropriate direction by relaxing tense muscles or activating muscles that are injured

In our research and practice, we use EMG training together with relaxation and imagery. This usually lasts about 20 min, during which the athlete is connected to the EMG feedback system and is able to fulfill the task of controlling EMG level

. Thus, for example, Krueger, Ruehl, Scheel, and Frdnz (1988)used EMG biofeedback to optimisetechnique with the new “wing” Kayak paddle, by encouraging greater use of the latissimus dorsi, the “wing” muscles on the back. These interdisciplinary approaches, which draw substantially from both motor learning and biomechanics, represent an exciting new

One of the common aims in EMG biofeedback application is to evaluate the efficacy of EMG biofeedback training; that is, to verify that a mastery of self-regulation has been achieved for a given criterion. Several researchers (Blumenstein, Bar-Eli, & Tenenbaum, 1995, 1997a; Zaichkowsky & Fuchs, 1986) have proposed approximate guidelines, sum

It should be noted that biofeedback has received a new lease of “sporting life” via its increasing application to the development of technical expertise. EMG biofeedback is increasingly used to aid the development and fine tuning of technique, especially when an optimum pattern has been identified

Likewise, there are several important questions in EMG biofeedback applications for which there are no clear answers, among them: For how long and how quickly must one be able to lower or raise EMG activity (for example, in our approach athletes can change their EMG activity to 0.6pV during 1 min)? How many EMG training sessions must be held‘?For e