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Logarithmic power-frequency: an alternative method for EMG-based fatigue assesment.
Yassierli Y; Nussbaum MA
Human Factors and Ergonomics Society 47th Annual Meeting. Santa Monica, CA: Human Factors and Ergonomics Society, 2003 Oct; :1184-1188
The purpose of this study was to explore different methods of processing EMG signals with a goal of obtaining more sensitive measures of fatigue. Two groups of 28 and 16 participants performed isometric efforts in arm abduction and torso extension until exhaustion respectively at three exertion levels (30, 50, and 70% of maximum). Electromyographic signals were recorded from the middle deltoid muscle and the erector spinae muscles at the L4/L5 level for the first and second group, respectively. Three new parameters, peak amplitude frequency, slop of lower frequency, and slop of higher frequency, were derived from logarithmic power versus logarithmic frequency over a 20-200 Hz bandwidth. Changes of these parameters over time were found to be sensitive to fatigue and to different levels of exertion. The first two parameters were more sensitive than median power frequency during arm abductions, but less sensitive than mean power frequency. In torso extensions, the slope of higher frequency gave better performance than the slope of lower frequency. This alternative method appears to have promise for future EMG-based assessments of localized muscle fatigue.
Statistical-analysis; Ergonomics; Human-factors-engineering; Physical-stress; Physical-exercise; Musculoskeletal-system-disorders; Musculoskeletal-system; Muscles; Muscle-stress; Muscle-tension; Muscular-disorders; Humans; Analytical-processes
Grado Department of Industrial and Systems Engineerinng, Virginia Tech, 250 Durham Hall (0118), Blacksburg, VA, 24061
Human Factors and Ergonomics Society 47th Annual Meeting
Virginia Polytechnic Institute and State University