Children-Adult Comparisons of VO2 and HR Kinetics during Submaximum Exercise

Abstract

Oxygen uptake (VO₂) and heart rate (HR) kinetics for submaximum exercise were compared in prepubescent boys (mean age ± SD = 10.2 ± 1.28 years, N = 21) and adult men (30.0 ± 5.64 years, N = 21). Standard open circuit spirometric techniques were used to determine _VO2 and a bipolar ECG was used to measure HR. The kinetics of VO₂ and HR were determined for each subject using graphic procedures. Subjects performed submaximum exercise on the bicycle ergometer at an intensity of 42 ± 1.3% (mean ± SE) of VO₂ max for the children and 39 ± 0.7% of VO₂ max for the adults (p = .07). There were no group differences in VO₂ t1/2 (children t1/2 = 18.5 ± 0.75 secs and adults t1/2 = 17.4 ± 0.39 secs, p = .18) and HR t1/2 (children t1/2 = 11.4 ± 1.86 secs and adults t1/2 = 13.6 ± 1.66 secs, p = .38). These data suggest that children and adults do not differ in cardiorespiratory adjustments during low intensity exercise. This is in contrast to suggestions of other investigators that children have a faster cardiovascular adjustment to exercise.     

基于标准的评核：教育领域人力资本和能力提升的工具与方法

本文概述了一种评核概念和理论,即基于标准的评核。这种评核模式通过把学生的成绩和他们的知识、课程标准联系起来,给学生的学习成绩赋予意义。它有效地将评核的焦点从对成绩排名的关注（仅仅把学生的表现与同学相比较）转移到了对学生学习进步的关注上来。本文关注这一转变过程,并为这一评核方式的实施提供可能的策略。同时,本文认为这一评核体系将会对教育中人力资本和能力提升产生深远的影响。     

运动能力与生物钟及分子生物学研究进展

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