Sensitive ages for physical fitness development

Physical fitness testing in Singapore is mandatory from age 9 years old till 18 years old in schools. Time and effort are spent annually in training for these tests as schools are ranked according to the test results and pupil obesity rate. There are natural rhythms and tempos for the development of physical capabilities but these remain unexplained in the Singaporean context. Identification of these ＂sensitive time periods＂ for fitness development will help PE teachers be more realistic about young people＇ s physical fitness and allow for a more balanced approach in the conduct of PE in schools.     

Reliability and validity of a talent identification test battery for seated and standing Paralympic throws

Paralympic throwing events for athletes with physical impairments comprise seated and standing javelin, shot put, discus and seated club throwing. Identification of talented throwers would enable prediction of future success and promote participation; however, a valid and reliable talent identification battery for Paralympic throwing has not been reported. This study evaluates the reliability and validity of a talent identification battery for Paralympic throws. Participants were non-disabled so that impairment would not confound analyses, and results would provide an indication of normative performance. Twenty-eight non-disabled participants (13 M; 15 F) aged 23.6 years (±5.44) performed five kinematically distinct criterion throws (three seated, two standing) and nine talent identification tests (three anthropometric, six motor); 23 were tested a second time to evaluate test–retest reliability. Talent identification test–retest reliability was evaluated using Intra-class Correlation Coefficient (ICC) and Bland–Altman plots (Limits of Agreement). Spearman’s correlation assessed strength of association between criterion throws and talent identification tests. Reliability was generally acceptable (mean ICC = 0.89), but two seated talent identification tests require more extensive familiarisation. Correlation strength (mean r_s = 0.76) indicated that the talent identification tests can be used to validly identify individuals with competitively advantageous attributes for each of the five kinematically distinct throwing activities. Results facilitate further research in this understudied area.     

Increasing plantarflexion angle during landing reduces vertical ground reaction forces,loading rates and the hip’s contribution to support moment within participants

The ankle joint’s role in shock absorption during landing has been researched in many studies, which have found that landing with higher amounts of plantarflexion (PF) results in lower peak vertical ground reaction forces and loading rates. However, there has not yet been a study that compares drop landings within participants along a quantitative continuum of PF angles. Using a custom-written real-time feedback program, participants adjusted their ankles to an instructed PF angle and dropped onto two force platforms. For increasing PF, peak ground reaction force and peak loading rate during weight acceptance decreased significantly. The hip’s contribution to peak support moment decreased as PF at initial contact increased up to 30°. The ankle and knee contributions increased over this same continuum of PF angles. There appears to be no optimal PF angle based on peak ground reaction force and loading rate measurements, but there may be an optimum where joint contributions to peak support moment converge and the hip moment’s contribution is minimised.     

教育是否能够改变社会――专访美国威斯康辛大学麦迪逊校区课程与教学系Michael W.Apple教授

李晓军:在美国,有相当部分人认为,美国的基础教育之所以落后,是因为缺乏"共同文化"基础上的统一课程标准,然而当前美国推行的以"标准化测试"为特征的教育改革,也受到反对者的批评。"标准化测试"的利弊得失在美国国内成为争论的焦点。那么在您看来,当前美国正在实施的国家课程与标准化测验政策,社会的反响如何?教育的成功与否真的能通过标准化测试进行测量吗?