The effect of 14 weeks of vitamin D3 supplementation on antimicrobial peptides and proteins in athletes

Heavy training is associated with increased respiratory infection risk and antimicrobial proteins are important in defence against oral and respiratory tract infections. We examined the effect of 14 weeks of vitamin D₃ supplementation (5000 IU/day) on the resting plasma cathelicidin concentration and the salivary secretion rates of secretory immunoglobulin A (SIgA), cathelicidin, lactoferrin and lysozyme in athletes during a winter training period. Blood and saliva were obtained at the start of the study from 39 healthy men who were randomly allocated to vitamin D₃ supplement or placebo. Blood samples were also collected at the end of the study; saliva samples were collected after 7 and 14 weeks. Plasma total 25(OH)D concentration increased by 130% in the vitamin D₃ group and decreased by 43% in the placebo group (both P = 0.001). The percentage change of plasma cathelicidin concentration in the vitamin D₃ group was higher than in the placebo group (P = 0.025). Only in the vitamin D₃ group, the saliva SIgA and cathelicidin secretion rates increased over time (both P = 0.03). A daily 5000 IU vitamin D₃ supplement has a beneficial effect in up-regulating the expression of SIgA and cathelicidin in athletes during a winter training period, which could improve resistance to respiratory infections.     

Explaining match outcome in elite Australian Rules football using team performance indicators

The relationships between team performance indicators and match outcome have been examined in many team sports, however are limited in Australian Rules football. Using data from the 2013 and 2014 Australian Football League (AFL) regular seasons, this study assessed the ability of commonly reported discrete team performance indicators presented in their relative form (standardised against their opposition for a given match) to explain match outcome (Win/Loss). Logistic regression and decision tree (chi-squared automatic interaction detection (CHAID)) analyses both revealed relative differences between opposing teams for “kicks” and “goal conversion” as the most influential in explaining match outcome, with two models achieving 88.3% and 89.8% classification accuracies, respectively. Models incorporating a smaller performance indicator set displayed a slightly reduced ability to explain match outcome (81.0% and 81.5% for logistic regression and CHAID, respectively). However, both were fit to 2014 data with reduced error in comparison to the full models. Despite performance similarities across the two analysis approaches, the CHAID model revealed multiple winning performance indicator profiles, thereby increasing its comparative feasibility for use in the field. Coaches and analysts may find these results useful in informing strategy and game plan development in Australian Rules football, with the development of team-specific models recommended in future.     

The effects of physical contact type on the internal and external demands during a rugby league match simulation protocol

The aim of this study was to investigate how the type of contact influences physiological, perceptual and locomotive load during a simulated rugby league match. Eleven male university rugby league players performed two trials of the rugby league movement simulation protocol for interchange forwards with a traditional soft tackle bag and a weighted tackle sled to replicate contact demands. The interchange forward-specific simulation was chosen given the contact frequency is higher for this group of players compared to whole match players. Locomotive rate, sprint speed, tackle intensity, heart rate (HR) and rating of perceived exertion were analysed during the first and second bouts that replicated two ~23 min on-field passages. Countermovement jump (CMJ) was measured before and immediately after each trial. More time was spent in heart rate zone between 91 and 100% HR_peak during the first (effect size ± 90% confidence interval: 0.44 ± 0.49) and second bouts (0.44 ± 0.43), and larger (0.6 ± 0.69) decrements in CMJ performance were observed during the sled trial (5.9, s = 4.9%) compared to the bag trial (2.6, s = 5.4%). Changing the type of contact during the match simulation subtly altered both the internal and external loads on participants. Using a standard tackle bag results in faster sprint speed to contact, but lower overall high-intensity running. Conversely, a heavier tackle object increases the internal load and results in greater lower limb neuromuscular fatigue as reflected by the decrease in CMJ performance.     

Remote ischaemic preconditioning shortens QT intervals during exercise in healthy subjects

The protective action of remote ischaemic preconditioning (RIPC) has been demonstrated in the context of surgical interventions in cardiology. Application of RIPC to sports performance has been proposed, but its effect on the electrocardiogram (ECG) during exercise remains unknown. This exploratory study aims to measure the changes in ventricular repolarization observed during exercise following RIPC in healthy subjects. In an experimental randomized crossover study, 17 subjects underwent two bouts of constant load exercise tests at 75% and 115% of gas exchange threshold (GET). Prior to exercise, they were allocated to either control or RIPC intervention with four cycles of 5?min of ischaemia followed by 5?min of reperfusion. ECG was continuously recorded during the protocol. QT and RR intervals were measured every 30?s (on an average tracing of the preceding 10?s). Although the time course of RR intervals did not differ between the two interventions (p?=?.56 at 75% GET and p?=?.74 at 115% GET), a significant shortening of QT intervals (measured from Q onset to T end) was observed during exercise (mean?±?standard deviation of RIPC vs. control: ?32?±?19?ms at 75% GET (p?p?p?p?相似文献   

Examining the effect of positive behaviour support on academic achievement of students with disabilities

Students who engage in challenging behaviour compromise the fundamental ability of schools to educate children. Consequently, teachers face the daunting task of designing effective strategies to promote positive educational outcomes for their students. Since the 1997 Individuals with Disabilities Education Act amendments, the use of positive behaviour supports (PBS) to address the behavioural needs of children challenged by disabilities has expanded. There is evidence to support the utility of PBS in reducing challenging behaviour among students. However, successful schools are also gauged by the academic achievement of their students. Hence, it is important to examine the extent to which behavioural outcomes are related to academic outcomes. The purpose of this paper is to examine the extent to which PBS interventions aimed at reducing challenging behaviour result in corresponding improvement in academic achievement. A meta‐analysis of extant research indicated a positive correlation of 0.40 between improvement in problem behaviour and academic achievement. A video abstract of this article can be viewed at: http://youtu.be/c9OUU0GkGrw .     

Grant‐maintained Heads’ Reflections on Opting Out

This article summarises the views of 222 grant‐maintained (GM) school's head teachers’ experience of, and reasons for, their schools opting out of local authority control. The survey was conducted on the first 499 secondary schools to go GM. The article investigates issues such as admissions, finances and also the effects of GM status (GMS) on the relationships with, and roles of, local education authorities, the Department for Education, parents and governors. The article provides an overview of moves to GMS and highlights prior aims and reflections.     

Impact of Anatomy Boot Camp on Students in a Medical Gross Anatomy Course

Lincoln Memorial University‐DeBusk College of Osteopathic Medicine (LMU‐DCOM) offers an optional three‐week summer Anatomy Boot Camp course (ABC) to facilitate students' transition into medical school and promote retention of anatomy subject matter. The pre‐matriculation program is a supplemental instruction course that utilizes a small group learning format. Boot camp instruction is led by teaching assistants and two anatomy professors. Enrollees gain early exposure to Medical Gross Anatomy (MGA) course subject matter, which is taught in the fall semester, and learn study skills necessary to excel in medical school. No grade is assigned for the course, therefore participants can study without the fear of potentially affecting grades. This study evaluates the effectiveness of the LMU‐DCOM ABC course using data from four consecutive summers. Independent two‐sample t‐tests were used to compare ABC to non‐ABC students for the following variables: incoming grade point average (GPA) and Medical College Admission Test® (MCAT®) scores, MGA written and laboratory practical examination grades, and final MGA course grade. Additionally, a 26‐question survey was administered to 2012–2014 boot camp participants. There were no significant differences in incoming GPA and MCAT scores. However, boot campers scored significantly higher on the first two lecture and laboratory examinations (P < 0.05) for each year of the study. Thereafter scores varied less, suggesting a faster head start for boot camp participants. Mean MGA final grade was on average 3% higher for the boot camp cohort. The survey feedback supports that the ABC course assists with the academic and social transition into medical school. Anat Sci Educ 10: 215–223. © 2016 American Association of Anatomists.