Development of an algorithm for assessing muscle fatigue on the basis of an analysis of the shape of the EMG power spectrum

Project manager: Danuta Roman-Liu Ph.D. (Eng.), D.Sc. (Eng.)

Project summary:

The aim of the task was to develop a coefficient of the shape of the EMG power spectrum that expresses changes related to muscle fatigue and to develop a method of assessing it on the basis of that indicator.The effects of the experimental study and an analysis of its results made it possible to was established that: - the parameters of the shape of the power spectrum are different between individual muscles,- both the duration of the load and the change in the level of force have an effect on the values of the parameters used so far in assessing fatigue,- on the basis of the EMG power spectrum, it is possible to determine parameters which will be more unequivocal than the RMS parameter used so far in indicating changes resulting from muscle tension without considering the processes that take place during the load,- from among the parameters suggested to be used in assessing fatigue or changes in muscle force, the field of frequency bands, characteristic border frequencies and the width of the power spectrum are useful,- the frequency for which the value of the normalized power spectrum is 0.2 and the parameter that expresses the width of the spectrum at the 0.3 level are the most general parameters of the shape of the spectrum that can be used in assessing fatigue,- by using the EMG power spectrum, it is possible to determine parameters that characterize fatigue. They are more unequivocal than the parameters used so far, they indicate changes caused by the duration of muscle load without considering changes caused by changes in the level of muscle force.An algorithm for assessing fatigue with the use of surface electromyography was developed. It has been prepared in the form of a practical guide.

Unit: Department of Ergonomics

Duration: 01.01.2005 – 30.11.2007