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171.
Road criterium and track bicycle racing occur at high speeds, demand repeated high power outputs, last 10–90?min, and offer little chance for recovery after the event. Consecutive evenings of criterium and track racing are respectively known as speed-week or six-day events and take place in evening hours over the course of a week. Given the schedule and timing of these competitions, return to homeostasis can be compromised. No recommendations exist on how to optimize recovery for cyclists participating in these types of repeated evening competitions. Criterium and track cyclists spend considerable time, near and above the individual lactate threshold and therefore mostly utilize carbohydrate as their chief energy substrate. Henceforth, pre – and post-race nutrition and hydration is examined and recommendations are brought forward for carbohydrate, protein, and fluid intake. As evening high-intensity exercise perturbs sleep, strategies to optimize sleep are discussed and recommendations for an optimal sleep environment are given. Active recovery is examined, and the benefits of a short duration low intensity exercise reviewed. Passive recovery methods such as compression garments and cold water immersion are recommended, while evidence for massage, pneumatic compression devices, and neuromuscular electrical stimulation is still lacking. Optimizing recovery strategies will facilitate a return to the resting state following strenuous night competition. 相似文献
172.
John Warmenhoven Stephen Cobley Conny Draper Andrew Harrison Norma Bargary Richard Smith 《Sports biomechanics / International Society of Biomechanics in Sports》2019,18(3):317-341
The proliferation of new biomechanical technology in laboratory and field settings facilitates the capture of data-sets consisting of complex time-series. An understanding of the appropriate statistical approaches for analysing and interpreting these data-sets is required and the functional data analysis (FDA) family of statistical techniques has emerged in the biomechanical literature. Given the use of FDA is currently in its infancy with biomechanical data, this paper will form the first of a two part series aiming to address practical issues surrounding the application of FDA techniques in biomechanics. This work focuses on functional principal components analysis (fPCA), which is explored using existing literature and sample data from an on-water rowing database. In particular methodological considerations for the implementation of fPCA such as temporal normalisation of data, removal of unwanted forms of variation in a data-set and documented methods for preserving the original temporal properties within a set of curves are explored in detail as a part of this review. Limitations and strengths of the technique are outlined and recommendations are provided to encourage the appropriate use of fPCA within the field of applied sports biomechanics. 相似文献
173.
AbstractThis paper examines the key elements within the relationships of sport and civil society in Scandinavia. The analysis combines themes and developments in Nordic sport and civil society, such as the role of the welfare state and the impacts of neoliberalism, with consideration of specific national experiences, especially in Finland. The discussion has four main parts. First, we set out the principal features of the ‘Nordic model’ of society, and how it shapes sport and civil society relations. Second, we advance a Finnish case study, examining the historical connections of three sectors to the national sport culture. Third, we consider how, in recent decades, the Nordic model has encountered and sought to respond to neoliberalism and globalization processes. Finally, we explore how Nordic societies have sought to influence globalization processes and ‘global civil society’ through sport, specifically through taking lead roles within the transnational ‘sport for development and peace’ sector. 相似文献
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175.
Scott Ailliet Rik Vandenberghe Toon Schiemsky Lode Van Overbeke Philippe Demaerel Wouter Meersseman David Cassiman Pieter Vermeersch 《Biochemia medica : ?asopis Hrvatskoga dru?tva medicinskih biokemi?ara / HDMB》2022,32(2)
Vitamin B12 deficiency can present with neurologic and psychiatric symptoms without macrocytic anaemia. We describe a case of late-onset cobalamin C deficiency which typically presents with normal serum vitamin B12 concentrations, posing an additional diagnostic challenge. A 23-year-old woman with decreased muscle strength and hallucinations was diagnosed with ‘catatonic depression’ and admitted to a residential mental health facility. She was referred to our hospital for further investigation 3 months later. Heteroanamnesis revealed that the symptoms had been evolving progressively over several months. Magnetic resonance imaging (MRI) of the brain showed diffuse symmetrical white matter lesions in both hemispheres. Routine laboratory tests including vitamin B12 and folic acid were normal except for a slight normocytic, normochromic anaemia. Over the next 6 weeks her symptoms deteriorated, and she became unresponsive to stimuli. A new MRI scan showed progression of the white matter lesions. The neurologist requested plasma homocysteine (Hcys) which was more than 8 times the upper limit of normal. Further testing revealed increased methylmalonic acid and the patient was diagnosed with adult-onset cobalamin C deficiency. This case illustrates that Hcys and/or methylmalonic acid should be determined in patients presenting with neuropsychiatric symptoms suggestive of vitamin B12 deficiency with a normal serum vitamin B12 to rule out a late-onset cobalamin C deficiency. 相似文献
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178.
Richard R. Valencia 《Psychology in the schools》1979,16(3):448-453
The present study compares the nonverbal intellectual performance as measured by the Raven's Coloured Progressive Matrices of 68 Chicano and 28 Anglo third-grade boys. An important aspect of the study was the attempt to control for problems related to SES, language status of the subjects, and cultural content of the testing instrument. The null hypothesis of no difference was rejected, as the Anglo group scored significantly higher than did the Chicano group. The results were discussed in terms of ω2 (omega square), a measure of statistical association. Because only 4% of the variance of the Raven's scores could be accounted for by ethnicity, it was concluded that the ethnicity variable does not effectively predict intelligence. 相似文献
179.
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
180.
John D. Van Buren 《Journal of The Franklin Institute》1866,81(4):219-223