New insights in paediatric exercise metabolism

Research in paediatric exercise metabolism has been constrained by being unable to interrogate muscle in vivo. Conventionally, research has been limited to the estimation of muscle metabolism from observations of blood and respiratory gases during maximal or steady state exercise and the analysis of a few muscle biopsies taken at rest or post-exercise. The purpose of this paper is to review how the introduction of ³¹P-magnetic resonance spectroscopy and breath-by-breath oxygen uptake kinetics studies has contributed to current understanding of exercise metabolism during growth and maturation. Methodologically robust studies using ³¹P-magnetic resonance spectroscopy and oxygen uptake kinetics with children are sparse and some data are in conflict. However, it can be concluded that children respond to exercise with enhanced oxygen utilization within the myocyte compared with adults and that their responses are consistent with a greater recruitment of type I muscle fibres. Changes in muscle metabolism are age, maturation- and sex-related and dependent on the intensity of the exercise challenge. The introduction of experimental models such as “priming exercise” and “work-to-work” transitions provide intriguing avenues of research into the mechanisms underpinning exercise metabolism during growth and maturation.     

Addressing the wicked problem of behaviour in schools

Behaviour management is an influential educational cliché in Australia, Canada, England, New Zealand and US. In practice, efforts to control student conduct in schools frequently utilise a manage-and-discipline model: a misinformed but deeply rooted set of interconnected notions about how to ensure an orderly and productive classroom. Students with disabilities affecting their behavioural development or who have mental health (MH) difficulties frequently face disadvantage, suspension or exclusion as a result of the application of this model in practice. Accommodating the behavioural needs of this population and at the same time, enabling their inclusion therefore represents a significant wicked problem for education in Australia, Canada, England, New Zealand and US. Evidence-based initiatives designed to address this dilemma in the US since the late 1990s, using PBS (Positive Behaviour Support) and also SWPBS (School-Wide Positive Behaviour Support), are outlined but the conclusion is reached that these efforts do not appear to have been successful. Recommendations are made for progress in tackling this wicked problem and include: wholehearted rejection of the manage-and-discipline model by practitioners; targeted support for teachers experiencing (or at risk of experiencing) occupational burnout; and the introduction of tangible educational policy incentives intended to encourage schools to include students who might otherwise face suspension or exclusion on behavioural grounds. Finally, this article advocates radical change in attitudes by teachers towards student conduct in schools and argues that educational practice should align with insights about human behaviour arising from research in developmental psychology.     

与青少年有氧能力相关的10个问题

峰值摄氧量（pVO2）是国际公认的青少年有氧能力评估标准,尽管有近八十年的青少年数据,但对它的解释以及它与青少年儿童成长和成熟过程中其他健康相关变量的关系,仍存在争议。有关青少年有氧能力可训练性的争论从未停止,仍然需要解决训练导致变化的因果机制以及根据年龄、生物性成熟、性别等因素进行调整。青少年日常体育活动的特点是间歇性进行和强度的迅速变化,但大多数青少年很少进行用来确定峰值摄氧量的强度和持续时间的体育活动。在这个背景下,肺部摄氧量的瞬态动力学就可以最好地反映青少年的有氧能力。对不同强度运动开始时青少年肺部摄氧量动力学的严格研究非常少,而在运动强度的阶跃变化中,实足年龄、生物性成熟和性别因素的影响并没有得到充分证实。了解青少年肺部摄氧量动力学参数的可训练性主要基于对运动员和非运动员的少量比较研究,对训练导致变化的根本机制仍需进一步探索。文章的目标是对成长和成熟过程中的有氧能力提供简要概述,提高对其评估和解释争议的认识,找出知识差距,提出10个相关的研究问题,并指出未来研究的潜在领域。     

对《与青少年有氧能力相关的10个问题》一文评论的回应

针对Dotan对《与青少年有氧能力相关的10个问题》的点评和后续讨论而得的《儿童有氧运动能力可训练性及相关问题》一文进行反馈,对Dotan提出的“现有的最大耗氧量数据的有效性”“儿童有限的有氧运动可训练性——是事实还是虚构？”“缺乏长期、纵向训练研究”“没有对儿童成年人的训练进行直接比较”“对儿童们声称的可训练性较低的合理解释”“训练质量”“其他可能的影响”“缺乏VO2稳定期”“肺部VO2动力学（pVO2）”“未来研究”几方面问题进行逐一解答,以强调《与青少年有氧能力相关的10个问题》（下简称《10个问题》）一文的讨论重点为青少年有氧适能的发展,而非儿童—成人差异。以成年人为研究对象的部分相关文献并未收录入《10个问题》中,因此Dotan的许多评论对于《10个问题》一文属于次要意见,需要在此特定背景下加以考虑。     

#SELFIES at the 2016 Rio Olympics: Comparing Self-Representations of Male and Female Athletes from the U.S. And China

Social media provides athletes an efficient platform on which to build and maintain their online image. Applying the self-representation theory of Goffman (1959), this study explored the gendered differences between the self-portrayals of U.S. and Chinese athletes. Findings suggest that hegemonic gender norms still had a strong hold on Chinese athletes’ self-disclosure, whereas minimal gender differences emerged between male and female U.S. athletes. Results suggested that cultural background had a substantial impact on self-representation for all participants. Although athletes might claim agency when presenting themselves on social media, the practice of self-portrayal should be examined within specific cultural contexts.