A good work environment can support companies' competitiveness, but many managers mostly associate ergonomics with occupational health and safety. In the process of managing the work environment and creating a good working environment, company managers have a central role. This article investigated managers' own descriptions of the work environment management (WEM). The study group consisted of successful companies (n=142) in a county of Sweden. The managers' descriptions were categorised into nine categories. The most frequently described category was “PhysicalFactors at work”, followed by “Manuals and Standardisation”, and “EmployeeInvolvement and Interaction”.
In an experimental study four levels of oculomotor load were induced binocularly. Trapezius muscle activity was measured with bipolar surface electromyography and normalized to a submaximal contraction. Twenty-eight subjects with a mean age of 29 (range 19–42, std 8) viewed a high-contrast fixationt arget for four 5-min periods through: (i) 3.5 dioptre (D) lenses; (ii) 0 D lenses; (iii) individuallya djusted prism D lenses (1–2 D base out); and (iv) +3.5 D lenses. The target was placed close to thei ndividual’s age-appropriate near point of accommodation in conditions (i–iii) and at 3 m in condition( iv). Each subject’s ability to compensate for the added blur was extracted via infrared photorefraction measurements. A bitwise linear regression model was fitted on group level with eye-lens refraction on the x-axis and normalized trapezius muscle EMG (%RVE) on the y -axis. The model had a constant level of trapezius muscle activity – where subjects had not compensated for the incurred defocus by a change in eye-lens accommodation – and a slope, where the subjects had compensated. The slope coefficient was significantly positive in the D (i) and the +D blur conditions (iv). During no blur (ii) and prism blur (iii) there were no signs of relationships. Nor was there any sign of relationship between the convergence response and trapezius muscle EMG in any of the experimental conditions. The results appear directly attributable to an engagement of the eye-lens accommodative system and most likely reflect sensorimotor processing along its reflex arc for the purpose of achieving stabilization of gaze
The purpose of this experimental study was to investigate if sustained periods of oculomotor load impacts on neck/scapular area muscle activity. The static trapezius muscle activity was assessed from bipolar surface electromyography, normalized to a submaximal contraction. Twenty-eight subjects with a mean age of 29 (range 19–42, SD 8) viewed a high-contrast fixation target for two 5-min periods through: (1) -3.5 dioptre (D) lenses; and (2) 0 D lenses. The target was placed 5 D away from the individual’s near point of accommodation. Each subject’s ability to compensate for the added blur was extracted via infrared photorefraction measurements. Subjects whose accommodative response was higher in the -D blur condition (1) showed relatively more static bilateral trapezius muscle activity level. During no blur (2) there were no signs of relationships. The results indicate that sustained eye-lens accommodation at near, during ergonomically unfavourable viewing conditions, could possibly represent a risk factor for trapezius muscle myalgia.