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131.
Abstract

The aim of the study was to assess the relationship between performance-based and laboratory tests for muscular strength and power assessment in older women. Thirty-two women aged 68.8 ± 2.8 years were recruited. All participants were asessed for: (a) two performance-based tests – the box-stepping test (mean 296 ± 51 J) and two-revolution maximum test (mean 7.1 ± 2 kg) performed while pedalling on a cycle ergometer; and (b) muscular function tests – maximal instantaneous peak power jumping on a force platform (mean 1528 ± 279 W); maximal voluntary contraction (MVC) during knee extension (mean 601 ± 571 N) and leg press (mean 626 ± 126 N), and leg press power (mean 483 ± 98 W) on a dynamometer. Using univariate analysis, performance-based tests were compared with laboratory muscle strength and power measurements. Muscle power correlated most strongly with the performance-based tests for both jumping and leg press power (r-values between 0.67 and 0.75; P < 0.01). The correlation with muscle strength measures ranged between 0.48 and 0.61 (P < 0.01). The proposed tests may have particular relevance in geriatric and rehabilitation environments as they represent an easy, practical, and inexpensive alternative for the assessment of muscular strength and power.  相似文献   
132.
Abstract

A cross-sectional study was carried out to analyse, through a limited number of fitness tests, the main conditioning and coordinative abilities in children aged 8–9 years, and their relationship with gender, anthropometric variables and physical activity habits. The height and weight of 256 boys and 241 girls were measured and information about physical activity habits was collected using a self-administered questionnaire. Physical performance was assessed by means of a few standardised tests: ‘sit & reach’, medicine-ball forward throw, standing long jump, 20 m running speed, and forward roll test. In both boys and girls, body weight and Body Mass Index (BMI) were positively correlated with the medicine-ball throw performances and negatively correlated for the standing long jump and speed tests, while no association was found with tests measuring back flexibility and total body coordination. Daily physical activity and participation in sport were not significantly correlated with body weight and BMI, but were positively associated with children's motor performance. The standardised fitness tests selected in the current study have been found to be suitable to identify fitness levels of primary school children. Thanks to their limited number and ease of measurement, they can be used in any school context to classify children and for monitoring the effects of targeted interventions promoting physical activity.  相似文献   
133.
ABSTRACT

Water polo players require a high level of upper-extremity strength, flexibility and coordination to achieve a peak level of throwing performance. Increased levels of shoulder proprioceptive acuity, strength and range of motion (ROM) have been previously associated with higher sporting performance. A coach-rating scale, used to quantify an athlete’s kicking proficiency in soccer; was adapted in the current study to measure each coach’s subjective expert opinion regarding athletes’ throwing mechanics, velocity, and accuracy. To examine this hypothesis shoulder proprioception acuity of 18 water polo players was measured both in-water and on-land using an AMEDA apparatus and correlated with coach-rated throwing performance and clinical measures of shoulder strength and ROM. There was a moderate positive correlation between the in-water and the on-land proprioception acuity (r = 0.47, p < 0.05). The in-water score showing a strong positive correlation with coach rated throwing mechanics (r = 0.68, p < 0.05) and velocity (r = 0.75, p = 0.02), suggesting that superior proprioception acuity contributed to fast, mechanically-efficient throwing. These findings support the notion that in-water proprioceptive acuity is an important determinant of the throwing performance achieved by water polo athletes and its measurement may be a valuable adjunct to current athlete screening.  相似文献   
134.
135.
In 28 male Caucasian nonprofessional ultracyclists, we investigated whether anthropometry or training volume had an influence on race speed in the 600 km at the Swiss Cycling Marathon 2007. Anthropometric parameters (age, body mass, body height, skin-fold thicknesses) were determined before the race to calculate body mass index and percent body fat. In addition, participants, using a training diary, recorded their training volume in hours and kilometers in the 3 months before the race. The influence of anthropometry and training volume on speed in the race as the dependent variable was investigated in a multiple linear regression model. Anthropometry showed a moderate association with speed in the race (r2 = .178, p < .05), whereas training volume showed no association (r2 = .000, p > .05). We concluded that anthropometry had a greater influence on race performance than training volume in recreational ultraendurance cyclists.  相似文献   
136.
Several composite indexes grouping several variables into a single figure have been proposed for measuring the digital divide. In this article, the authors analyze shortcomings of extant indexes. Using multivariate analysis tools, they show that in the definition of composite indexes it is possible to individuate a limited set of more influencing and significant variables. This finding suggests the possibility of replacing some redundant variables with other dimensions that include other aspects of the digital divide that are not considered in extant measures.  相似文献   
137.
Given the crucial role of suppliers in collaborative supply chains, it is surprising that little attention has been paid to the nature and management of supplier relationships in the implementation of a retailer's Customer Relationship Management (CRM) strategy. To address this gap in the extant literature, the theory of organizational justice is used to explore the extent to which perceived fairness in buyer–supplier relationships supports or inhibits supplier engagement with the CRM process. The rationale is that suppliers who feel fairly treated by key retail customers are more likely to invest resources in the acquisition and use of data central to the retailer's CRM strategy. By empirically testing a conceptual model linking downstream CRM to upstream SRM, the results provide evidence to indicate that customer data use is significantly influenced by perceptions of fairness, particularly with respect to the distribution of rewards, and the transparency of decision-making processes. As a key criticism of CRM centers upon the failure of organizations to exploit the full potential of customer data, the results highlight the usefulness of understanding the relational linkages between buyers and suppliers and the consequential behavior of suppliers in terms of engagement with customer data vital to the success of retailers’ CRM strategies.  相似文献   
138.
This paper examines how the relationship between firm value and patent-based indicators of inventive activity has changed over time. We use data from more than 33,000 mergers and acquisitions deals between 1985 and 2007, and distinguish between American (USPTO) and European (EPO) patents. Our results indicate that over time EPO patents have become the dominant indicator of innovative activity, while USPTO patents have no effect on firm value near the end of the sample period. The results are robust to controlling for citations and are especially strong for small firms, for firms operating in the drug and chemical industries, and when target and acquiring firms operate in different industries or countries.  相似文献   
139.
Emotional responses from local community groups to the establishment of new industrial activities, involving toxic chemicals, are common. The need for more public education about chemical hazards has often been stated. In the eastern suburbs of Melbourne, PCBs have been stored since 1985, pending their destruction. Council approval for the siting of a pilot plant for their treatment recently caused controversy. This paper presents an analysis of the situation, defines the knowledge needed by ordinary people to participate effectively and rationally in decision making and discusses the acquisition of that knowledge in a community setting. It is not the intention of the author to discuss the contribution that could be made through formal secondary education. Specializations: primary science teacher education, computers in education, environmental education, social responsibility in science.  相似文献   
140.
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