Technological advances, modified work practices, altered employment strategies, work-related injuries, and the rise in work-related litigation and compensation claims necessitate ongoing trade analysis research. Such research enables the identification and development of gender- and age-neutral skills, physiological attributes and employment standards required to satisfactorily perform critical trade tasks. This paper overviews a methodological approach which may be adopted when seeking to establish trade-specific physiological competencies for physically-demanding trades (occupations). A general template is presented for conducting a trade analyses within physically-demanding trades, such as those encountered within military or emergency service occupations. Two streams of analysis are recommended: the trade analysis and the task analysis. The former involves a progressive dissection of activities and skills into a series of specific tasks (elements), and results in a broad approximation of the types of trade duties, and the links between trade tasks. The latter, will lead to the determination of how a task is performed within a trade, and the physiological attributes required to satisfactorily perform that task. The approach described within this paper is designed to provide research outcomes which have high content, criterion-related and construct validities.
The purpose of this study was to clarify the characteristics of the physiological response that occurs while walking in water and on land at an exercise intensity based on the rating of perceived exertion (RPE) in elderly men. Nine elderly men ranging from 66–70 years of age participated in this study as subjects. The actual trials consisted of walking for 20 minutes in 31°C and 35°C water on an underwater treadmill. The water depth of the treadmill corresponded to the level of the xiphoid process in the subject. The same subjects performed on-land walking using a moving belt treadmill for 20 minutes at a room temperature of 27°C. The exercise intensity during walking in the two water trials and the on-land trial was the same “somewhat hard” measured on the basis of the subject's RPE rating of 13. There was no significant difference between the subjects' rectal temperatures among the three trials. The mean skin temperature and mean body temperature while walking for 20 minutes in 35°C water were significantly higher (P<0.01) than in 31°C water and on land. There were no significant differences in oxygen uptake and heart rate among the two trials in water and the on-land trial. The above results suggest that the exercise intensity based on a subject's RPE may be an effective index for the prescription of thermoneutral water walking in the same way that it is for land walking in the elderly.
The present paper aims to investigate two characteristics; task performance and muscular load during skill process for the pen-tablet input system with the mouse input system on the PC in order to determine the comprehensive usability for the pen-tablet system. Two computer tasks were designed for the study: task SL and task PT. Task SL was a repetitive computer-drawing including typical mouse motions such as clicking and drag-dropping. Task PT was a polgon tracing task requiring fine-controlled movements with the input device. Surface electromyography (EMG) and performance data were measured during the task. When the pen-tablet was being used, low amplitudes of EMGs for the biceps brachii, the flexor digitorum superficialis, and the extensor digitorum were found, whereas no EMG difference for the trapezius was found for both tasks. On the first day, the performance with the mouse was much higher than the performance with the pen-tablet in terms of error rates and the number of completed trials. However, the performance with the pen-tablet exceeded the performance with the mouse from the second day on, and the subjects performed better with the pen-tablet than with the mouse. Current results imply that the skill process for the pen-tablet system was very short and the subjects felt comfortable to use the new system from the beginning.
Body mass index (BMI) is widely used as an index of obesity in people from the school age children to adults. However, the relationship between the change in BMI with age and the coming of menarche has not been discussed as there are few reports on the changes in BMI with age. In this study, the change in BMI with age was examined by applying the wavelet interpolation method (WIM), and a critical period for body fat in terms of the coming of menarche was estimated from the growth velocity. We investigated delayed menarche according to the influence of stress in athletes by comparing delayed menarche between athletes and non-athletes in relation to the critical period. Data were obtained from 144 female athletes in their first year at university in the Tokai area, all of whom had competed in a national sports competition in high school (athlete group). Health examination records showing these subjects' heights and weights from the first grade of elementary school to the final year of high school (1984–1995) were collected and BMI was calculated for each grade. Ages at menarche were ascertained from questionnaires. A control group of 73 non-athletes was similarly examined. The age at maximum peak velocity (MPV) derived from the growth (aging) distance curve of BMI was determined in the control group to be 11.96±0.97 years old. This age at MPV of BMI was almost the same as the age at menarche (12.11±0.93 years old). Therefore, this age at MPV of BMI is estimated to be the critical period of body fat for the coming of menarche. The interval between the age at MPV of BMI and age at menarche was 0.74±1.30 years in the athlete group and 0.15±0.81 years in the control group, so there was a significant difference (P<0.01) between the two groups. It is suggested that the delayed menarche in athletes is influenced by the stress of regular sports training.
The present study is aimed to clarify the degree of leanness desired by contemporary young Japanese women using questionnaires and to use allometry to define the body weight boundary between the excessively lean and the others for a given height. Questionnaires on ideal body shape were distributed to female college students living in Akita and the suburbs of Tokyo. Data for 578 respondents, aged 18 to 21 years-old, were analyzed. The questionnaire asked the subjects to report their current and ideal body shape and to make a qualitative self-assessment of their weight. On average, the perceived ideal weight was 5.2 kg lower than the current weight. The results also revealed that young women have a tendency to misunderstand their body shape and to regard themselves as heavier than they really were. Meanwhile, we defined leanness as a state of insufficient lean body mass (LBM, kg) in relation to height (Ht, cm). Allometric equation of LBM on Ht and the standard error of estimate (SEE) were calculated as LBM=3.87×10−3×Ht1.826 and 1.09, respectively. The LBM boundary between the excessively lean and the others was determined using these values according to a statistical procedure comparing normal and abnormal values. The corresponding total body weight was estimated from the boundary LBM in the literature. Subsequently the body weight boundary for each height was tabulated in order to make young women reconsider weight control. The subjects were asked to assess the body weight boundary for their own height. The boundary values were found to be consistent with the sense of the subjects.