Nutrition for the young athlete     

Meyer F  O'Connor H  Shirreffs SM;International Association of Athletics Federations 《Journal of sports sciences》2007,25(Z1):S73-S82

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   

Physique and performance for track and field events     

O'Connor H  Olds T  Maughan RJ;International Association of Athletics Federations 《Journal of sports sciences》2007,25(Z1):S49-S60

Evidence of the importance of physique in the athletics disciplines is supported by the persistence of certain characteristics over long periods, despite marked secular changes in the source population. These characteristics may also result in physiological benefits such as effective thermoregulation or a greater power-to-weight ratio. Coaches and athletes are often convinced of weight or fat loss benefits based on personal or anecdotal experience, intuition, and "trained eye" observation of successful competitors. This may entice athletes into adopting unbalanced, erratic or highly restrictive eating patterns that increase the risk for nutrient deficiencies, and disordered eating. Despite heavy training loads and often extreme diets, some athletes fall short of their physique goals as ultimately phenotype is under genetic control. Professionals assisting athletes with physique management need to be highly skilled in anthropometry and require a thorough understanding of sports-specific nutrition requirements. Careful assessment of the risks and benefits of various approaches to weight and fat loss is required before they are recommended to athletes.  相似文献   

The effects of extrinsic reinforcement on intrinsic motivation     

Richard A. Blocker  R. P. Edwards 《Psychology in the schools》1982,19(2):260-268

In this paper, the role of extrinsic reinforcement in intrinsic motivation is discussed in terms of Deci's cognitive attribution theory. The competing response hypothesis and the frustration hypothesis are presented as alternative modes of analysis. “Undermining” is the phenomenon proposed by the cognitive attribution theorists that accounts for reported decrements in intrinsically motivated behaviors following external rewards. The literature regarding undermining in token economy research is critically evaluated. The author concludes that: (a) Cognitive attribution theory lacks parsimony, in that extant reinforcement analysis can account for undermining with equal facility. (b) Undermining is of little significance as a concept, due to its elusive and transient impact on operant behavior.  相似文献   

Job burnout and the school psychologist     

Helen D. Reiner  Timothy S. Hartshorne 《Psychology in the schools》1982,19(4):508-512

School psychologists participating in a workshop on burnout completed Freudenberger's Burnout Questionnaire (1980), identified major job-related stressors, and responded to a list of suggested supervisory, individual, and organizational strategies for prevention. Slightly less than half of the participants appeared on the questionnaire to have burnout problems. Age, years of experience, and sex were not significantly related to the burnout score. Major identified stressors included excessive caseloads, lack of time, and lack of support or appreciation. Reactions to the strategies were positive and hopeful. Implications for training were drawn.  相似文献   

Making better performance easier with multisource assessment     

Mark R. Edwards  Ann J. Ewen 《Performance Improvement》1995,34(2):20-22

  相似文献   

Hidden in the Mix: The African American Presence in Country Music Diane Pecknold,Editor. Durham,NC: Duke University Press, 2013.     

Leigh H. Edwards 《Journal of American culture (Malden, Mass. : 2003)》2014,37(3):358-359

  相似文献   

Short-term reliability of inflammatory mediators and response to exercise in the heat     

Joshua H. Guy  Andrew M. Edwards  Catherine M. Miller  Glen B. Deakin  David B. Pyne 《Journal of sports sciences》2017,35(16):1622-1628

Prospective application of serum cytokines, lipopolysaccharide (LPS), and heat shock proteins (eHSPs) requires reliable measurement of these biomarkers that can signify exercise-induced heat stress in hot conditions. To accomplish this, both short-term (7 day) reliability (at rest, n = 12) and the acute responsiveness of each biomarker to exercise in the heat (pre and post 60-min cycling, 34.5°C and 70% RH, n = 20) were evaluated. Serum was analysed for the concentration of C-reactive protein (CRP), interleukin-6 (IL-6), heat shock protein 72 (eHSP72), immunoglobulin M (IgM) and LPS. Test–retest reliability was determined as the coefficient of variation (CV). Biomarkers with the least short-term within-participant variation were IL-6 (19%, ±20%; CV, ±95% confidence limits (CL)) and LPS (23%, ±13%). Greater variability was observed for IgM, eHSP72 and CRP (CV range 28–38%). IL-6 exhibited the largest increase in response to acute exercise (95%, ±11%, P = < 0.001) and although CRP had a modest CV (12%, ±7%), it increased substantially post-exercise (P = 0.02, ES; 0.78). In contrast, eHSP72 and LPS exhibited trivial changes post-exercise. It appears variation of common inflammatory markers after exercise in the heat is not always discernible from short-term (weekly) variation.  相似文献   

The chemical basis of plant forms     

Helen C. De. S. Abbott 《Journal of The Franklin Institute》1887,124(3):161-185

  相似文献   

The efflux of gases through small orifices     

Edgar Buckingham  Junius David Edwards 《Journal of The Franklin Institute》1920,189(2):244

  相似文献   

Children's heart rate reactivity responses to three school tasks     

Christopher F. Sharpley  Geraldine M. Parsons  Helen Tillinh 《Psychology in the schools》1989,26(4):411-414

The effects of three routine classroom tasks upon heart rate reactivity were investigated with a sample of 30 typical fifth-grade children. Instructions for a mental arithmetic task, the mental arithmetic task itself, and silent reading were administered under standardized conditions, with a reward being offered for performance on the mental arithmetic task to enhance competition. Heart rate was individually monitored each second during these tasks, and data were collected on mental arithmetic performance and reading ability. Results indicated that some children showed large increases in their heart rates during the three tasks, and that these children should be considered as at-risk in terms of their cardiac health.  相似文献