Correlations Among Five Demographic Variables and the Performance of Selected Jamaican 11th-graders on Some Numerical Problems on Energy

This study was designed to assess whether the level of performance of selected Jamaican 11th-grade physics students on some numerical problems on the energy concept was satisfactory and if there were significant differences in their performance linked to their gender, socioeconomic background (SEB), school location, English language and mathematical abilities. The 331 sampled students consisted of 213 boys and 118 girls; 197 students were from a high SEB and 134 students from a low SEB; 296 students were from seven urban schools and 35 students from three rural schools; 112, 153 and 66 of the students had high, average and low English language abilities, respectively, while 144, 81 and 106 of the students had high, average and low mathematical abilities, respectively. An Energy Concept Test (ECT) consisting of six structured numerical questions was employed for data collection. The results indicated that although the students’ level of performance was regarded as fairly satisfactory, there was a lot of room for improvement. There were statistically significant differences in the students’ performance on the ECT linked to SEB, and mathematical abilities in favour of students from a high SEB, and high mathematical abilities, respectively. There was a positive, statistically significant but weak correlation between the students’ (a) mathematical abilities, and (b) English language abilities and their performance on the ECT, while there were no correlations among their gender, school location, and SEB and their performance on the ECT.     

Digitizing journal archives: the experience of Taylor & Francis

There are enormous quantities of information available to researchers on the Internet, of varying levels of quality. Now, more than ever, it is important that academic publishers make best use of their journals and provide their readers with access to this high‐value content, in a form that can be easily found and used. To that end, Taylor & Francis have taken up the challenge of satisfying researchers' need to have all relevant content available at their fingertips, by digitizing their older journal content, creating subject‐based collections of backfiles and putting them online. This article provides an insight into the ‘why’ and ‘how’ of the process of digitization of Taylor & Francis's journal archives. The fact that these online backfiles are being requested, purchased, and used demonstrates the added value that publishers may hold in their archives.     

The Challenges of Supporting Equity Literacy Skill Development in White Teacher Candidates: A Self-Study of Two White Field Instructors

In classrooms, race-based bias, discrimination, and inequities result in unsafe and unproductive learning environments. Teacher educators are charged with helping preservice teachers develop racial literacy skills. This self-study explores the ways in which two White teacher educators recognize and attempt to manage challenges during field instruction of White teacher candidates. The teacher educator researchers explore their own Whiteness and use a racial lens to critique their practices. Post-lesson-debriefing conferences between teacher educators and their candidates are shared as illustrative vignettes to reveal instructors’ teaching challenges and failures. Implications for working with White teacher candidates, improvements to field instruction practices, student teaching curricula revisions, and programmatic changes are posited.     

Effects of a short-term pre-season training programme on the body composition and anaerobic performance of professional rugby union players

Abstract

Pre-season rugby training develops the physical requisites for competition and consists of a high volume of resistance training and anaerobic and aerobic conditioning. However, the effects of a rugby union pre-season in professional athletes are currently unknown. Therefore, the purpose of this investigation was to determine the effects of a 4-week pre-season on 33 professional rugby union players. Bench press and box squat increased moderately (13.6 kg, 90% confidence limits ±2.9 kg and 17.6 ± 8.0 kg, respectively) over the training phase. Small decreases in bench throw (70.6 ± 53.5 W), jump squat (280.1 ± 232.4 W), and fat mass (1.4 ± 0.4 kg) were observed. In addition, small increases were seen in fat-free mass (2.0 ± 0.6 kg) and flexed upper-arm girth (0.6 ± 0.2 cm), while moderate increases were observed in mid-thigh girth (1.9 ± 0.5 cm) and perception of fatigue (0.6 ± 0.4 units). Increases in strength and body composition were observed in elite rugby union players after 4 weeks of intensive pre-season training, but this may have been the result of a return to fitness levels prior to the off-season. Decreases in power may reflect high training volumes and increases in perceived of fatigue.     

Influence of vitamin D mushroom powder supplementation on exercise-induced muscle damage in vitamin D insufficient high school athletes

Abstract

Incidence of vitamin D deficiency is increasing worldwide. The purpose of this study was to determine if supplementation with vitamin D₂ from Portobello mushroom powder would enhance skeletal muscle function and attenuate exercise-induced muscle damage in low vitamin D status high school athletes. Participants were randomised to Portobello mushroom powder (600 IU/d vitamin D₂) or placebo for 6 weeks. Participants then completed a 1.5-h exercise session designed to induce skeletal muscle damage. Blood samples and measures of skeletal muscle function were taken pre-supplementation, post-supplementation/pre-exercise and post-exercise. Six weeks supplementation with vitamin D₂ increased serum 25(OH)D₂ by 9.9-fold and decreased serum 25(OH)D₃ by 28%. Changes in skeletal muscle function and circulating markers of skeletal muscle damage did not differ between groups. In conclusion, 600 IU/d vitamin D₂ increased 25(OH)D₂ with a concomitant decrease in 25(OD)D₃, with no effect on muscular function or exercise-induced muscle damage in high school athletes.     

Handling pressures: analysing touch in American films about youth sport

This paper examines how films produced in the USA in the past 10 years and featuring the coaching of youth sport, represent the issue of touch during instruction and training. Touch in such films is figured in diverse ways ranging from pats of reassurance and hugs of congratulation to cuffs of disapprobation. Touch is also occasionally depicted differently, dependent upon the ethnicity and gender of the central characters in specific films. These distinctions are evaluated for what they reveal about the nuances of understandings of touch in film portrayals of sport education in American high schools. The difficulty of interpreting physical contact between coaches and athletes in these films, and what this reveals about the problem of policing touch in general in educational settings, is explored. Finally, the paper examines how the films expose the intricacy of tactile encounters in ways that challenge the judiciousness of risk-averse ‘no-touch’ policies and practices in sports coaching.     

A Tutorial on Centering in Cross-Sectional Two-Level Models

The primary purpose of this tutorial is to succinctly review some options for, and consequences of, centering Level 1 predictors in commonly applied cross-sectional two-level models. It is geared toward both practitioners and researchers. A general understanding of multilevel modeling is necessary prior to understanding the subtleties of centering decisions. A review of some high-quality journals within the broad discipline of exercise science provides evidence that multilevel modeling is used relatively infrequently in this field. Therefore, a secondary purpose is to introduce Measurement in Physical Education and Exercise Science readers to some core facets of multilevel modeling within the framework of this tutorial. A relevant dataset is used to demonstrate potential consequences of different centering decisions within a multilevel model. Depending on the model and the data, different centering decisions can exert non-trivial influence on the meaning of some model parameters, results from fitting the model, and subsequent conclusions.     

Effect of the coefficient of friction of a running surface on sprint time in a sled-towing exercise

This study investigated the effect of the coefficient of friction of a running surface on an athlete's sprint time in a sled-towing exercise. The coefficients of friction of four common sports surfaces (a synthetic athletics track, a natural grass rugby pitch, a 3G football pitch, and an artificial grass hockey pitch) were determined from the force required to tow a weighted sled across the surface. Timing gates were then used to measure the 30-m sprint time for six rugby players when towing a sled of varied weight across the surfaces. There were substantial differences between the coefficients of friction for the four surfaces (μ = 0.21–0.58), and in the sled-towing exercise the athlete's 30-m sprint time increased linearly with increasing sled weight. The hockey pitch (which had the lowest coefficient of friction) produced a substantially lower rate of increase in 30-m sprint time, but there were no significant differences between the other surfaces. The results indicate that although an athlete's sprint time in a sled-towing exercise is affected by the coefficient of friction of the surface, the relationship relationship between the athlete's rate of increase in 30-m sprint time and the coefficient of friction is more complex than expected.