Normalisierung der EMG-Aktivität des M. trapezius mithilfe submaximaler Referenzkontraktionen: Schwierigkeiten und Lösungsansätze

Zusammenfassung: Submaximale Referenzkontraktionen (RVE) sind bei elektromyographischen (EMG) Messungen des M. trapezius eine international empfohlene Normalisierungsmethode. Die vorliegende Publikation zeigt mögliche Schwierigkeiten dieser Methode und Lösungsansätze auf. Das EMG von 20 Pflegefachangestellten wurde erfasst und mittels submaximaler RVE normalisiert. Es ergab sich ein signifikanter Zusammenhang der Erholzeit und des 10. Perzentils des EMG zu RVE. Dies kann zu einer systematischen Verfälschung der Resultate führen. Mögliche Wege diese Verfälschung abzuschwächen sind das Einbeziehen von RVE in das statistische Modell, eine Verschiebung der gesamten Verteilung oder den Ausschluss von Messungen ausserhalb einer von uns vorgeschlagenen Bandbreite für RV

Leg and back muscle activity, heart rate, performance and comfort during sitting, standing, and using a sit-stand-support with different seat angles

Long-lasting sitting and standing is related to several health risks and alternatives to these positions are needed. This study compared muscle activity, heart rate, performance, and comfort between sitting, standing, and using a stable sit-stand-support with four different seat angles. Twenty-one subjects fulfilled three tasks (typing, a tweezing task and a task simulating ironing) in every position for five minutes. The heart rate was higher using a sit-stand-support and standing compared to sitting. The activity of the m. erector spinae was similar or lower using a sit-stand-support compared to sitting or standing. The activity of the m. gastrocnemius was in between the levels of sitting or standing. No significant differences were observed for the performance. The sit-stand-support most often was preferred to sitting. A stable sit-stand-support may be a solution for short interruptions of sitting or standing. Relevance to industry A stable sit-stand-support may be an option for short interruptions of sitting and standing and may reduce the consequences of these static positions

Joint position error after neck protraction-retraction movements in healthy office workers : a cross-sectional study

Since the upper cervical spine (UCS) has been regarded to be distinct from the lower cervical spine (LCS), joint position error (JPE) needs to be tested separately for both regions. The purpose of this study was to investigate the JPE after cervical protraction/retraction movements, involving opposite movements of extension and flexion for the UCS and LCS. These movements are frequently performed during office work. Cervical JPEs were tracked in thirty healthy office workers while performing four tests of cervical pro-retraction movements with variations in vision and movement direction, and assessed using the Kinect head tracker (Microsoft Corp), placed in front of each participant. The JPE was expressed in constant (CE), absolute (AE) and variable errors (VE). Multilevel linear models evaluated main and interaction effects of vision, movement direction, cervical region and sex. Slightly larger JPEs have been found in the UCS. Vision showed no effect on any outcome variable. No effect exceeded typical measurement errors reported for the Kinect head tracker. This study showed, that JPEs after pro-retraction movements of the head and neck may differ for UCS and LCS. The differences were small and not beyond measurement error reported for the Kinect

Mediterranean diet intervention alters the gut microbiome in older people reducing frailty and improving health status : the NU-AGE 1-year dietary intervention across five European countries

Objective Ageing is accompanied by deterioration of multiple bodily functions and inflammation, which collectively contribute to frailty. We and others have shown that frailty co-varies with alterations in the gut microbiota in a manner accelerated by consumption of a restricted diversity diet. The Mediterranean diet (MedDiet) is associated with health. In the NU-AGE project, we investigated if a 1-year MedDiet intervention could alter the gut microbiota and reduce frailty. Design We profiled the gut microbiota in 612 non-frail or pre-frail subjects across five European countries (UK, France, Netherlands, Italy and Poland) before and after the administration of a 12-month long MedDiet intervention tailored to elderly subjects (NU-AGE diet). Results Adherence to the diet was associated with specific microbiome alterations. Taxa enriched by adherence to the diet were positively associated with several markers of lower frailty and improved cognitive function, and negatively associated with inflammatory markers including C-reactive protein and interleukin-17. Analysis of the inferred microbial metabolite profiles indicated that the diet-modulated microbiome change was associated with an increase in short/branch chained fatty acid production and lower production of secondary bile acids, p-cresols, ethanol and carbon dioxide. Microbiome ecosystem network analysis showed that the bacterial taxa that responded positively to the MedDiet intervention occupy keystone interaction positions, whereas frailty-associated taxa are peripheral in the networks. Conclusion Collectively, our findings support the feasibility of improving the habitual diet to modulate the gut microbiota which in turn has the potential to promote healthier ageing.Peer reviewe

Normalisierung der EMG-Aktivität des M. trapezius mithilfe submaximaler Referenzkontraktionen: Schwierigkeiten und LösungsansätzeNormalization of trapezius muscle EMG with submaximal reference contractions: difficulties and solution approaches

ISSN:0944-2502ISSN:0173-333