Adult musculoskeletal disorders (MSD) such as neck and low back pain have been widely reported as being of significant health and economic concern in industrialised countries. Recent literature has indicated that these disorders are also prevalent amongst school students. Student posture in classroom environments has been implicated as a risk factor for spinal MSD, but the relationship between student classroom postures and the development of subsequent adult MSD is unknown. Thus, this review examined the literature on school student (pupil) posture (five year olds through to university) in classroom environments, and its potential for predisposing adults to musculoskeletal conditions (particularly neck and low back pain) in their working life. The review is presented under the following five headings: student posture, anthropometrics and furniture; computer use; pain reporting; vision. The review indicated that all of these factors could influence the prevalence of MSD amongst pupils and suggested that any attempts to reduce MSD amongst school children should include an integrated ergonomics approach involving micro and macro ergonomic factors such as classroom furniture design, posture education, backpack weight and load carriage, learning systems re-organisation and general organisation of school activities. Although there was strong evidence that all five of the main factors examined in this review are related to MSD amongst school students, none of the papers reviewed provided any specific evidence that student MSD was related to subsequent MSD in adult life. It is therefore concluded that there was no clear objective evidence to support the view that there is a relationship between poor school posture and the development of neck and/or low back pain in adult working life.

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Objective: During training and other strenuous physical activity in the mountains, deserts, and other wilderness areas, those consuming pre-packaged rations or take-along-food often have difficulty maintaining adequate energy, water and electrolytes, and carbohydrate intakes. This study assessed the effects of ad libitum consumption of a carbohydrate beverage supplement (8% maltodextrin sweetened with aspartame) on energy and carbohydrate intakes of physically active test volunteers. Methods: Energy and carbohydrate intakes of volunteers randomly assigned to receive either a carbohydrate beverage supplement (CHO) (n=32) or a non-caloric placebo beverage (PLACEBO) (n=31) during an 11-day field training exercise were assessed. Mean total energy expenditure (TEE), water turnover (R_H2O), and total body water (TBW) were measured in a sub-group of volunteers (CHO: n=10, PLACEBO: n=9) using the stable isotopes ²H₂O and H₂¹⁸O. Results: The CHO group had greater daily energy intake (EI_CHO: 12.8±0.6 MJ/day; EI_PLACEBO: 11.0±0.8 MJ/day; p<0.05) and carbohydrate intake (CHO: 470±139 g/day; PLACEBO: 317±68 g/day; p<0.05). No differences were observed in TEE (TEE_CHO: 18.41±4.40 MJ/day; TEE_PLACEBO: 16.12±2.70 MJ/day), TBW (TBW_CHO: 46.9±5.5 L; TBW_PLACEBO: 44.5±3.3 L) or water turnover (R_H2O–CHO: 5.6±1.1 L/day; R_{H2O–PLACEBO}: 5.1±0.7 L/day) between groups. Discussion: Providing a carbohydrate beverage may reduce energy and CHO deficits that commonly occur during recreational treks or in those working for extended periods in wilderness environments.

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When accurately quantifying convective heat exchange between the human body and the surrounding environment, mean skin temperature is determined by measuring the skin temperature of areas of the body surface exposed to airflow (hereinafter referred to as the convective heat transfer area) and then calculating the ratio of the convective heat transfer area with the uniform skin temperature to the total convective heat transfer area. Thus we must consider convective heat transfer areas to determine mean skin temperature. In this study, the convective heat transfer area of the human body in two basic postures (standing on the floor and sitting on a chair) was measured by dividing the body surface into smaller sections. We then proposed weighting coefficients for calculating mean skin temperature taking into account convective heat transfer areas, and conducted experiments to clarify how convective heat transfer areas affected calculations of mean skin temperature. The results showed that, for both standing and sitting positions, due to the areas of contact between two body surfaces and between the body and the floor, the convective heat transfer area for the hand and foot regions was markedly small. We then calculated weighting coefficients for calculating mean skin temperature that take into account convective heat transfer areas for standing and sitting positions. The tendency was that the smaller the ratio of convective heat transfer area to the total body surface area, the greater the difference in mean skin temperature using the Hardy-DuBois technique. The results of the present study also clarify that by taking into account convective heat transfer areas, the skin temperature of the extremities can be reflected in mean skin temperature for both standing and sitting positions.

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In this paper a method to measure the moisture (water vapor) conductivity of clothing is proposed. The method is based on the wet cup method, which is often used for building materials. The proposed method overcomes the difficulty of applying the wet cup method to thin and air-permeable material like cloth by determining the surface moisture transfer resistances at both sides of cloth gravimetrically. Measured results on cotton cloth are shown.

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Residents of non-insulated houses in Kyoto were surveyed in the winter, spring and summer of 1992. The surveys measured room temperature and recorded residents' behavior. This study compares residents' behavior in spring, which is conventionally considered a neutral thermal environment, with residents' behavioral thermoregulation reacting to cold in winter and to heat in summer. Moreover, the relationships between room temperature and behavior are presented quantitatively, based on the measurement of room temperature. The results of the survey can be summarized as follows:
Since residents customarily heat only the living room, the time they stay there increases in winter. When houses are poorly insulated and heating appliances are inadequate, staying in the only heated room as a means of behavioral thermoregulation increases. Moreover, since even the warmth of the heated living room is inadequate, residents spend more time near heating appliances. Furthermore, since the temperature near the floor surface is lower still, there is regular use of a supplementary heating appliance designed for sitting down with on the floor. Because of the use of these devices sitting on the floor, time spent sitting on a chair or a sofa decreases in winter. Thus the lives of residents in winter are restricted by low room temperatures. However, avoiding heating other rooms and living with seasonal variations in room use are efficient and economical means of achieving thermal comfort.

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