| 1. |
- Cyrén, Henrik, et al.
(författare)
-
Task Specific Exposure Information as a Basis for Production System Design
- 1998
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- This publication was written during a period of time when the authors were engaged in an extensive research programme financed by the National Institute for Working Life in Solna (Cooperative for Optimisation of industrial production systems regarding Productivity and Ergonomics COPE).
|
|
| 2. |
|
|
| 3. |
- Forsman, Mikael, 1963, et al.
(författare)
-
Motor unit recruitment in the trapezius muscle with special reference to coarse arm movements.
- 2001
-
Ingår i: Journal of electromyography and kinesiology : official journal of the International Society of Electrophysiological Kinesiology. - 1050-6411 .- 1873-5711. ; 11:3, s. 207-16
-
Tidskriftsartikel (refereegranskat)abstract
- Chronic shoulder pain is common in a variety of occupations. The "Cinderella hypothesis" suggests that the pain originates from damaged type I muscle fibres driven into degenerative processes as a result of too long activation and too short recovery time. The main purpose of this study was to investigate if the same motor units are active during all phases of coarse arm movements. Eight healthy volunteers participated in the study. Intramuscular electromyographic signals were picked up with a four-lead fine wire electrode, during a unilateral straight arm movement. The movement started with either (part 1) an abduction or a flexion, then (2) a movement in the horizontal plane from the sagittal to the frontal plane or vice versa, and finally (3) an adduction or an extension to the start position. The movement cycle was performed in three different speeds, slow, medium, and high, with one, two or five cycles per 20 s, respectively. On an average, the motor unit action potentials (MUAPs) of 6 motor units (range, 1-15) were identified per trail. In total 94% of the MUAP trains that were identified showed firings in all 3 parts of the movements. The findings support the Cinderella hypothesis, although there is a need to further investigate the temporal pattern of long-term motor unit activity.
|
|
| 4. |
- Thorn, Stefan, 1971, et al.
(författare)
-
Trapezius muscle rest time during standardised computer work - A comparison of female computer users with and without self-reported neck/shoulder complaints
- 2007
-
Ingår i: Journal of Electromyography and Kinesiology. - : Elsevier BV. - 1873-5711 .- 1050-6411. ; 17:4, s. 420-427
-
Tidskriftsartikel (refereegranskat)abstract
- Work related musculoskeletal disorders (WMSDs) in the shoulder/neck area are a common and increasing problem among European computer workers, especially women. Long-term low-level workloads with low degree of muscle rest are a potential risk factor for developing WMSDs. The purpose of the present study of female computer users (age 45-65 years) in Denmark and Sweden was to investigate if subjects with self-reported neck/shoulder complaints (cases, N = 35) show less trapezius muscle relative rest time (RRT) than controls (N = 44) when performing standardised short-term computer work tasks in controlled laboratory conditions. Surface electromyography (EMG) signals were recorded bilaterally from the upper trapezius muscles during a type, edit, precision and colour word stress task. Besides RRT, 10th percentile RMS values were calculated. On the average, 15 of the cases and 18 of the controls showed analysable EMG files per task. For the colour word stress task, the results showed lower RRT values and higher 10th percentile RMS amplitude levels among cases compared to controls. No such signs could be found for the other tasks performed. The present results indicate an increased motor response to a psychological stressor among subjects with self-reported neck/shoulder complaints. (c) 2006 Elsevier Ltd. All rights reserved.
|
|
| 5. |
|
|
| 6. |
|
|
| 7. |
|
|
