Evidence for data missing at random in youth physical activity monitoring research     

P. F. Saint-Maurice  Y. Kim  G. J. Welk 《Journal of sports sciences》2017,35(5):484-490

This study examined whether or not activity monitor data collected as part of a typical 7-day physical activity (PA) measurement protocol can be expected to be missing at random. A total of 315 participants (9–18 years) each wore a SenseWear Armband monitor for 7 consecutive days. Participants were classified as “compliant” (86 boys and 124 girls) if they had recorded accelerometer data during 70% or more of the predefined awake time (7 AM–10 PM) on four different days; and “non-compliant” (44 boys and 51 girls) when not meeting these criteria. Linear mixed models were used to examine differences in energy expenditure (EE) levels by compliance across 10 different time periods. The results indicated that non-compliant girls were older (13.4 ± 2.9 vs. 12.2 ± 2.5) and taller (156.8 ± 10.3 vs. 152.8 ± 11.3) than their same gender compliant peers (P < .05). Comparisons of EE rates at segmented portions of the day revealed no differences between compliant and non-compliant groups (P ≥ .05). Differences in EE ranged from ?0.32 kcal · kg^?1 · h^?1 (before school time) to 0.62 kcal · kg^?1 · h^?1 (physical education class) in boys and ?0.39 kcal · kg^?1 · h^?1 (transportation from school) to 0.37 kcal · kg^?1 · hour^?1 (recess) in girls. The results showed that compliant and non-compliant individuals differed in a few demographic characteristics but exhibited similar activity patterns. This suggests that data were considered to be missing at random, but additional work is needed to confirm this observation in a representative sample of children using other types of activity monitors and protocols.  相似文献   

Approaches to the Byzantine Family     

Spyros P. Panagopoulos 《Al-Masaq: Islam & the Medieval Mediterranean》2016,28(2):211-214

  相似文献   

Allegany to Appomattox: The Life and Letters of Private William Whitlock of the 188th New York Volunteers Valgene Dunham. Syracuse,NY: Syracuse University Press, 2013.          下载免费PDF全文

Jeffrey P. Cain 《Journal of American culture (Malden, Mass. : 2003)》2015,38(3):276-277

  相似文献   

Unequal Prospects: Is Working Longer the Answer?     

E. Michael Brady 《Educational gerontology》2015,41(2):165-166

  相似文献   

Editor’s Comments: Introduction to Volume 66, Issue 3     

Mike W. Metzler 《Quest (Human Kinetics)》2014,66(3):247-248

  相似文献   

Points from the SENCo‐Forum: SENCos supporting parents          下载免费PDF全文

K. Wedell 《British Journal of Special Education》2017,44(4):484-487

  相似文献   

E.E. Fournier d’Albe’s Fin de siècle: Science,Nationalism and Monistic Philosophy in Britain and Ireland     

Ian B. Stewart 《Cultural and Social History》2017,14(5):599-620

The fin de siècle witnessed radical shifts in the intellectual and cultural landscapes of the British Isles in the context of a general revolt against Victorian values. E. E. Fournier d’Albe – physicist, spiritualist, inventor and Pan-Celticist – personified the ability of intellectuals to latch onto and advance new trends, made available by the emergent intellectual pluralism. Like many contemporaries he rejected traditional religion, but he also disdained scientific materialism, and sought a deeper metaphysical meaning to life, pursued through his various interests. Influenced by the totalising theories of figures like Herbert Spencer and Ernst Haeckel, Fournier concocted his own brand of scientific monism, rejecting materialism, embracing spiritualism, and ever optimistic in the notion of scientific progress, even in the wake of the carnage of the Great War. The article aims to give Fournier a fuller historical treatment, allowing his story to add to understanding of the milieus in which he lived and operated, and revealing how his monistic philosophy incorporated some of the disparate cultural strands explored by intellectuals in the fin de siècle reaction against conventional Victorian ideals.  相似文献   

The effects of attentional focus instructions on punching velocity and impact forces among trained combat athletes     

Israel Halperin  Dale W. Chapman  David T. Martin  Chris Abbiss 《Journal of sports sciences》2017,35(5):500-507

Research indicates that instructing athlete’s to focus on bodily movements (internal focus of attention [IFA]) may hinder performance, whereas instructing them to focus on the movement outcome (external focus of attention [EFA]) often enhances performance. Despite the importance of instructions in striking combat sports, limited research has examined the influence of IFA and EFA on performance in well-trained combat athletes. This study investigated the effects of different instructional cues on punching velocity (m · s^?1) and normalised impact forces (N · kg^?1) among intermediate (n = 8) and expert (n = 7) competitive boxers and kickboxers. Athletes completed three rounds of 12 maximal effort punches delivered to a punching integrator on three separate days. Day one was a familiarisation session with only control instructions provided. In the following two days athletes randomly received IFA, EFA or control instructions prior to each of the three rounds. Athletes punching with EFA were 4% faster and 5% more forceful than IFA (P < 0.05), and 2% faster and 3% more forceful than control (P < 0.05). Furthermore, experts punched 11% faster and with 13% greater force compared with intermediate athletes (P < 0.05). EFA led to a positive effect on punching performance and should be favoured over IFA and control instructions.  相似文献   

Piece-by-Piece Review of Digitize-and-Lend Projects through the Lens of Copyright and Fair Use     

Michelle M. Wu 《Legal Reference Services Quarterly》2017,36(2):51-73

Digitize-and-lend library projects can benefit societies in multiple ways, from providing information to people in remote areas or with physical disabilities to facilitating the sharing of library resources with information-poor communities. This article explores the potential of digitize and lend as well as outlines how projects can be undertaken in a manner respectful of the balance of copyright.  相似文献   

A novel sleep optimisation programme to improve athletes’ well-being and performance     

Emer Van Ryswyk  Richard Weeks  Laura Bandick  Michaela O’Keefe  Andrew Vakulin  Peter Catcheside 《European Journal of Sport Science》2017,17(2):144-151

Objectives: To improve well-being and performance indicators in a group of Australian Football League (AFL) players via a six-week sleep optimisation programme. Design: Prospective intervention study following observations suggestive of reduced sleep and excessive daytime sleepiness in an AFL group. Methods: Athletes from the Adelaide Football Club were invited to participate if they had played AFL senior-level football for 1–5 years, or if they had excessive daytime sleepiness (Epworth Sleepiness Scale [ESS] >10), measured via ESS. An initial education session explained normal sleep needs, and how to achieve increased sleep duration and quality. Participants (n?=?25) received ongoing feedback on their sleep, and a mid-programme education and feedback session. Sleep duration, quality and related outcomes were measured during week one and at the conclusion of the six-week intervention period using sleep diaries, actigraphy, ESS, Pittsburgh Sleep Quality Index, Profile of Mood States, Training Distress Scale, Perceived Stress Scale and the Psychomotor Vigilance Task. Results: Sleep diaries demonstrated an increase in total sleep time of approximately 20?min (498.8?±?53.8 to 518.7?±?34.3; p?<?.05) and a 2% increase in sleep efficiency (p?<?0.05). There was a corresponding increase in vigour (p?<?0.001) and decrease in fatigue (p?<?0.05). Conclusions: Improvements in measures of sleep efficiency, fatigue and vigour indicate that a sleep optimisation programme may improve athletes’ well-being. More research is required into the effects of sleep optimisation on athletic performance.  相似文献