At present there is very low to low quality evidence that sit-stand desks may decrease workplace sitting between thirty minutes to two hours per day without having adverse effects at the short or medium term. There is no evidence on the effects in the long term. There were no considerable or inconsistent effects of other interventions such as changing work organisation or information and counselling. There is a need for cluster-randomised trials with a sufficient sample size and long term follow-up to determine the effectiveness of different types of interventions to reduce objectively measured sitting time at work.

At present there is low-quality evidence that the use of sit-stand desks reduce workplace sitting at short-term and medium-term follow-ups. However, there is no evidence on their effects on sitting over longer follow-up periods. Effects of other types of interventions, including workplace policy changes, provision of information and counselling, and multi-component interventions, are mostly inconsistent. The quality of evidence is low to very low for most interventions, mainly because of limitations in study protocols and small sample sizes. There is a need for larger cluster-RCTs with longer-term follow-ups to determine the effectiveness of different types of interventions to reduce sitting time at work.

Chimpanzees possess a large number of behavioral and cultural traits among nonhuman species. The “disturbance hypothesis” predicts that human impact depletes resources and disrupts social learning processes necessary for behavioral and cultural transmission. We used a dataset of 144 chimpanzee communities, with information on 31 behaviors, to show that chimpanzees inhabiting areas with high human impact have a mean probability of occurrence reduced by 88%, across all behaviors, compared to low-impact areas. This behavioral diversity loss was evident irrespective of the grouping or categorization of behaviors. Therefore, human impact may not only be associated with the loss of populations and genetic diversity, but also affects how animals behave. Our results support the view that “culturally significant units” should be integrated into wildlife conservation.

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To cite this Article van DieËn, J. H. , De Looze, M. P. and Hermans, V. (2001) 'Effects of dynamic office chairs on trunk kinematics, trunk extensor EMG and spinal shrinkage ', Ergonomics, 44: 7,[739][740][741][742][743][744][745][746][747][748][749][750] To link to this Article: DOI: 10.1080/00140130120297 URL: http://dx.doi.org/10.1080/00140130120297Full terms and conditions of use: http://www.informaworld.com/terms-and-conditions-of-access.pdf This article may be used for research, teaching and private study purposes. Any substantial or systematic reproduction, re-distribution, re-selling, loan or sub-licensing, systematic supply or distribution in any form to anyone is expressly forbidden.The publisher does not give any warranty express or implied or make any representation that the contents will be complete or accurate or up to date. The accuracy of any instructions, formulae and drug doses should be independently verified with primary sources. The publisher shall not be liable for any loss, actions, claims, proceedings, demand or costs or damages whatsoever or howsoever caused arising directly or indirectly in connection with or arising out of the use of this material. Seated work has been shown to constitute a risk factor for low-back pain. This is attributed to the prolonged and monotonous low-level mechanical load imposed by a seated posture. To evaluate the potential health eOE ects with respect to the low back of o ce chairs with a movable seat and back rest, trunk kinematics, erector spinae EMG, spinal shrinkage and local discomfort were assessed in 10 subjects performing simulated o ce work. On three separate occasions subjects performed a 3 h task consisting of word processing, computer-aided design and reading. Three chairs were used, one with a ® xed seat and back rest and two dynamic chairs, one with a seat and back rest movable in a ® xed ratio with respect to each other, and one with a freely movable seat and back rest. Spinal shrinkage measurements showed a larger stature gain when working on the two dynamic chairs as compared with working on the chair with ® xed seat and back rest. Trunk kinematics and erector spinae EMG were strongly aOE ected by the task performed but not by the chair type. The results imply that dynamic o ce chairs oOE er a potential advantage over ® xed chairs, but the eOE ects of the task on the indicators of trunk load investigated were more pronounced than the eOE ects of the chair. EOE ects of dynamic o ce chairs on trunk kinematics