Forma, Vol. 29 (Special Issue), pp. S29S36, 2014

Study of Surface Electromyography and Its Indices to Evaluate Muscular Control

Hiroki Takada1,2*, Masumi Takada1, Yasuyuki Matsuura3, Masaru Miyao3 and Tomoki Shiozawa4

1Aichi Medical University School of Medicine, Nagakute, Aichi 480-1195, Japan
2Graduate School of Engineering, University of Fukui, 3-9-1 Bunkyo, Fukui 910-8507, Japan
3Graduate School of Information Science, Nagoya University, Furo-cho, Nagoya 464-8603, Japan
4School of Business, Aoyama Gakuin University, 4-4-25 Shibuya, Shibuya-ku, Tokyo 150-8366, Japan
*E-mail address:

(Received December 20, 2010; Accepted March 7, 2011)

Abstract. Human beings begin to lose the ability to control muscles with advancing age. A reduction in the function of flexor muscles is observed in the case of the elderly when they experience a fall. The flexor muscles around the hip joint include femoral rectus and abdominal muscles. Recently, there has been an increasing focus on biofeedback training (BFT), which is expected to improve the ability to control muscles and prevent the deterioration of muscular functions due to aging. In this study, we performed surface electromyography (sEMG) of the femoral rectus muscles during the BFT of a dominant leg. This study aimed at developing indices for form in a smoothed sEMG and evaluating the changes in these indices with age. Statistical analysis indicated that it was necessary to include the time constant of the exponential decay curve fit to maximal points during prolonged muscular contraction. A reduction in the ability to control muscles owing to aging can be detected by performing sEMG during BFT by using a time constant. This time constant will be applied to evaluate the effect of BFT on recovery of the ability.

Keywords: Surface Electromyography (sEMG), Biofeedback Training (BFT), Flexor Muscles, Aging, Double-Wayland Algorithm

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