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961.
Stürze im Alter     
The consequences of falls can be considerable for elderly people. They often lead to fractures or other injuries, immobility, curtailed independence, need for long-term care, and even death. They decrease the quality of life and can exert a negative influence on self-esteem, activity level, and the number of social contacts. The annual rate of falls in people over 65 is approximately 30%. This number increases to about 50% up to the age of 80 years and almost half of those who fall do so more than once during the course of a year. More than 90% of all falls occur in everyday situations, mostly resulting from movement errors. All studies demonstrated a significant correlation between muscle weakness and the incidence of falls, thus representing a major risk factor for a fall. Gait disorders, hip fractures, and the loss of functional autonomy are closely related to falls and associated with age to a similar extent. Almost 90% of hip fractures in Germany are the result of a fall. From the individual and economic points of view, a fracture near the hip has serious consequences in old age. Based on research findings to date, vibration training could constitute an interesting alternative to classic methods of strength training in fall prevention programs. The aim of this contribution is to provide fundamental facts regarding epidemiology and prevention and to present a potential approach to implementing vibration training in multimodal programs designed to prevent falls.  相似文献   
962.
The purpose of this paper was to begin understanding leadership within a major sporting event. A case study of the 2005 Fédération Internationale de Natation (FINA) World Aquatics Championships was built by means of interviews and archival material, using a multi-stakeholder perspective. Findings highlighted that core elements of upper-management level leadership in events were best described by the multiple-linkage leadership theory, which includes task commitment, ability and role clarity, work organization, cooperation and mutual trust, resources and support, and external coordination as the six intervening variables. While charismatic and transformational leadership styles surfaced as contributing to the overall success of an event, the multiple-linkage leadership theory offered a more comprehensive understanding of leadership in major sporting events from a multi-stakeholder perspective.  相似文献   
963.
Acknowledgements     

Acknowledgement

Acknowledgements  相似文献   
964.
Accurate measurement of physical activity is fundamentally important in epidemiological research of physical activity behavior A widely used telephone-based physical activity questionnaire was compared with other methods of administration and objective measures (pedometers and accelerometers) among 80 adults (43 women). The telephone questionnaire was comparable to both the self-administered form and international telephone-administered equivalent. Although moderate correlation coefficients with objective measures supported the use of the questionnaire, wide prediction intervals generated using Bland Altman methods highlighted large discrepancies between the measures, particularly in the moderate intensity category. These findings illustrate the limitations of correlation coefficients in validation studies and the inaccuracy of self-report questionnaires in measuring physical activity.  相似文献   
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967.
A sport-specific measure of moral disengagement was developed in 2 studies. In Study 1, a 59-item questionnaire was developed and tested with 308 athletes from 5 team sports. A series of confirmatory factor analyses (CFA) testing different models suggested the model that best fitted the data had 6 first-order factors that could be represented by 1 second-order factor. Study 2 involved 305 athletes from the same 5 sports. CFA confirmed the 6-factor, second-order structure for the final 32-item measure. Results from Study 2 supported the construct validity of the scale, providing evidence for the factorial, concurrent, convergent, and discriminant validity. The Moral Disengagement in Sport Scale (MDSS) is proposed as a valid and reliable measure of moral disengagement for use in the sport context.  相似文献   
968.
Although the importance of high motivation to engage in deliberate practice has been acknowledged, no research has directly tested this hypothesis. Therefore, the present study examined this relation in adolescent elite chess players by means of a questionnaire. In addition, to provide an explanation for dropout among promising chess players, differences in motivation between persistent and dropout chess players were analyzed. Competitiveness and the will to excel proved to be predictors of investments in deliberate practice. Moreover, achievement motivation and chess-specific motivation differed to a certain extent between persisters and dropouts. Our results suggest that motivation to engage in deliberate practice not only contains elements of the will to improve performance, but also of the will to attain exceptional levels of performance.  相似文献   
969.
Athletics is a popular sport among young people. To maintain health and optimize growth and athletic performance, young athletes need to consume an appropriate diet. Unfortunately, the dietary intake of many young athletes follows population trends rather than public health or sports nutrition recommendations. To optimize performance in some disciplines, young athletes may strive to achieve a lower body weight or body fat content and this may increase their risk for delayed growth and maturation, amenorrhoea, reduced bone density, and eating disorders. Although many of the sports nutrition principles identified for adults are similar to those for young athletes, there are some important differences. These include a higher metabolic cost of locomotion and preferential fat oxidation in young athletes during exercise. Young athletes, particularity children, are at a thermoregulatory disadvantage due to a higher surface area to weight ratio, a slower acclimatization, and lower sweating rate. An appropriate dietary intake rather than use of supplements (except when clinically indicated) is recommended to ensure young athletes participate fully and safely in athletics.  相似文献   
970.
This paper, which was part of the International Association of Athletics Federations (IAAF) 2007 Nutritional Consensus Conference, briefly reviews the components of the female athlete triad (Triad): energy availability, menstrual status, and bone health. Each component of the Triad spans a continuum from health to disease, and female athletes can have symptoms related to each component of the Triad to different degrees. Low energy availability is the primary factor that impairs menstrual dysfunction and bone health in the Triad. We discuss nutritional issues associated with the Triad, focusing on intakes of macronutrients needed for good health, and stress fractures, the most common injury associated with the Triad. Finally, we briefly discuss screening and treatment for the Triad and the occurrence of the Triad in men.  相似文献   
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