caa a22 4500 467941432 CHVBK 20180406153013.0 cr unu---uuuuu 170328e20060101xx s 000 0 eng 10.1007/s00421-004-1212-4 doi (NATIONALLICENCE)springer-10.1007/s00421-004-1212-4 Are changes in pain induced by myofeedback training related to changes in muscle activation patterns in patients with work-related myalgia? [Elektronische Daten] [Miriam Vollenbroek-Hutten, Hermie Hermens, Gerlienke Voerman, Leif Sandsjö, Roland Kadefors] The objective of this explorative study was to investigate to what extent changes in perceived pain, induced by myofeedback training, are correlated to changes in muscle activation patterns. Thirty subjects with work-related myalgia received myofeedback training. Before (T0), directly after (T1) and 4 weeks or, in a subset of patients, 3 months after (T2) this training, surface electromyography (sEMG) measurements of the upper trapezius muscle were performed during standardized computer tasks; a typing and a stress task. Besides this, visual analogue scales (VAS) were filled in to assess the levels of pain in the neck and shoulders. From the sEMG, root mean square (RMS) and relative rest time (RRT, i.e. the percentage of time RMS is below a certain threshold) were used for data analysis. The relationships between RRT, RMS and VAS at T0 as well as for the changes between T1-T0 and T2-T0 were investigated using Spearman correlation coefficients. The results revealed no significant correlations between VAS and RMS both at baseline (range R =−0.22 to 0.17) and for the observed changes (range R =−0.33 to 0.32). Also, for VAS and RRT, low correlations were found for baseline (range R =−0.27 to 0.21) and for changes between T1-T0 (range R =−0.02 to 0.38). However, for the changes between T2-T0, correlation coefficients for the VAS for the shoulder and the RRT of the right trapezius during both the typing and stress tasks were significant at the P =0.05 level, whereas the correlation coefficients for the VAS for the neck and both the left and right trapezii during the stress task approached significance ( P =0.05 and P =0.1, respectively). These results suggest that decreases in pain observed at long term follow up after myofeedback training might occur as a result of an increased ability to relax but not as a result of decreased muscle activation level. However, the largest correlation found was 0.6. This means that the maximal explained variance ( R 2) is low (36%), and that there are also other processes than the changes in muscle activation that contribute to changes in perceived pain. Springer-Verlag, 2004 Myofeedback nationallicence Pain nationallicence Muscle relaxation nationallicence EMG activity nationallicence Vollenbroek-Hutten Miriam Roessingh Research and Development, Roessinghsbleekweg 33b, 7522 AH, Enschede, The Netherlands aut Hermens Hermie Roessingh Research and Development, Roessinghsbleekweg 33b, 7522 AH, Enschede, The Netherlands aut Voerman Gerlienke Roessingh Research and Development, Roessinghsbleekweg 33b, 7522 AH, Enschede, The Netherlands aut Sandsjö Leif National Institute for Working/Life West, Gotheborg, Sweden aut Kadefors Roland National Institute for Working/Life West, Gotheborg, Sweden aut European Journal of Applied Physiology Springer-Verlag 96/2(2006-01-01), 209-215 1439-6319 96:2<209 2006 96 421 https://doi.org/10.1007/s00421-004-1212-4 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s00421-004-1212-4 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Vollenbroek-Hutten Miriam Roessingh Research and Development, Roessinghsbleekweg 33b, 7522 AH, Enschede, The Netherlands aut NATIONALLICENCE 700 1- Hermens Hermie Roessingh Research and Development, Roessinghsbleekweg 33b, 7522 AH, Enschede, The Netherlands aut NATIONALLICENCE 700 1- Voerman Gerlienke Roessingh Research and Development, Roessinghsbleekweg 33b, 7522 AH, Enschede, The Netherlands aut NATIONALLICENCE 700 1- Sandsjö Leif National Institute for Working/Life West, Gotheborg, Sweden aut NATIONALLICENCE 700 1- Kadefors Roland National Institute for Working/Life West, Gotheborg, Sweden aut NATIONALLICENCE 773 0- European Journal of Applied Physiology Springer-Verlag 96/2(2006-01-01), 209-215 1439-6319 96:2<209 2006 96 421 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer