Exercise oxidative metabolism in children.

尽管儿科运动生理学领域的文献如雨后春笋般涌现，但关于调节儿童和青少年运动过程中氧化代谢的因素的知识仍然难以捉摸。我们对儿童运动氧化代谢的了解主要来自对最大摄氧量的研究。儿童肌肉工作从休息到运动的转变最好通过肺摄氧量(PVO2)动力学反应来评估，肺摄氧量受氧的输送、提取和利用的调节。可以在工作到工作的转变、踏板节奏和吸入氧气浓度中使用操作来非侵入性地检查氧气摄取运输链上游(输送)或下游(提取和利用)组件的影响。因此，在接下来的5年里，我的目标是：(1)阐明年龄、性别和成熟度对运动中pVO2动态反应的影响(2)通过分离氧摄取运输链的上游(传递)和下游(利用)组件的影响来确定支撑外周机制的基础(3)在实现这些目标的过程中发展一个世界级的儿科‘运动氧化代谢’研究实验室*科学方法：*参与者将是健康的青春期前(~8-10岁)、青春期(12-16岁)和年轻人(18-24岁)。为了探索性别差异，所有群体中将有50%是男孩。我们将使用一些析因实验来探索在中强度和大强度运动转换中的pVO2动力学反应(I)在有和没有启动运动的情况下；(Ii)在常氧(21%)和低氧(15%)吸入O2浓度下，以及(Iii)当以55rpm和115rpm的速度踏板时。*新颖性和意义：*这项研究计划将提供有关以下方面的新信息：调节儿童对运动的能量挑战的氧化代谢反应的因素，女孩和男孩之间的差异，以及随着儿童的年龄和成熟，这种差异如何变化。这些研究的结果将极大地提高我们对性别差异反应以及生长发育对氧化功能的影响的认识，这可能会影响当前儿童和青少年运动氧化代谢的理论。重要的是，这项工作将创造一个更好的证据基础，以此为基础设计有效的干预措施，确定决定锻炼反应的生理因素以及这些因素可以改变的程度。这将是开展未来研究的关键，该研究将调查因疾病或环境而受损的氧化代谢。********

Despite the burgeoning literature in the field of pediatric exercise physiology, knowledge around the factors that regulate oxidative metabolism during exercise in children and adolescents remains elusive. Our understanding of exercise oxidative metabolism in the child has come mainly from studies of maximal oxygen uptake. The transitions in muscular work from rest to exercise in children are best assessed from the pulmonary oxygen uptake (pVO2) kinetic response, which is regulated by oxygen delivery, extraction and utilization. It is possible to use manipulations in work-to-work transitions, pedal cadence and the concentration of inspiratory oxygen to noninvasively examine the influence of upstream (delivery) or downstream (extraction and utilization) components of the oxygen uptake transport chain. Therefore, over the next 5 years, my objectives are to: (1) to elucidate the influence age, sex and maturation have on the pVO2 kinetic response during exercise (2) to identify underpinning peripheral mechanisms by isolating the impact of upstream (delivery) and downstream (utilization) components of the oxygen uptake transport chain (3) in achieving these develop a world-class pediatric `exercise oxidative metabolism' research laboratory at UBC Okanagan******SCIENTIFIC APPROACH: ***Participants will be healthy prepubertal (~8-10 years), pubertal (12 to 16 years) and young adults (18-24 years). To allow for sex differences to be explored all groups will be 50% boys. We will use a number of factorial experiments to explore the pVO2 kinetic response during moderate and heavy intensity exercise transitions (i) with and without priming exercise; (ii) during normoxic (21%) and hypoxic (15%) inspiratory O2 concentrations, and (iii) when pedaling at 55 rpm and at 115 rpm. ******NOVELTY AND SIGNIFICANCE:***This research programme will provide new information about the factors that regulate the oxidative metabolic response to the energetic challenges of exercise in the child, how this differs between girls and boys and how this changes as the child ages and matures. The results from these studies will significantly advance our knowledge of sex-differentiated responses and the influence growth and development have on oxidative function, which has the potential to influence current theories of exercise oxidative metabolism in the child and adolescent. Importantly this work will create a better evidence base from which effective intervention can be designed, establishing the physiologic factors that determine the response to exercise and the degree to which these can be altered. This will be key to developing future research investigating impaired oxidative metabolism due to disease or environment. ********