The effect of ball-carrying technique and experience on sprinting in rugby union

There are several ways of carrying the ball in rugby union, which could influence the speed at which a player can run. We assessed 52 rugby players (34 males, 18 females) during a maximum sprint over 30 m without the ball, with the ball under one arm, and with the ball in both hands. Timing gates were used to measure time over the initial 10 m and the last 20 m. It has previously been reported (Grant et al., 2003) that running with the ball produces a slower sprinting speed than running without the ball. We hypothesized that the decrease in speed caused by carrying the ball would become less marked with the experience of the player. The male and female players were each divided into two groups: a "beginner" group that consisted of players in their first or second season and an "experienced" group that was composed of players who had played for more than two seasons. A 2 x 3 mixed-model analysis of variance was used to identify differences (P < 0.01) between the beginner and experienced groups in the three sprinting conditions. The times for the males for the first 10 m sprints without the ball, with the ball under one arm, and with the ball in both hands were 1.87 +/- 0.08 s, 1.87 +/- 0.08 s, and 1.91 +/- 0.1 s for the beginners, and 1.87 +/- 0.1, 1.88 +/- 0.1 and 1.88 +/- 0.12 for the more experienced players respectively. The times for the females for the first 10 m without the ball, with the ball under one arm, and with the ball in both hands were 2.13 +/- 0.16 s, 2.19 +/- 0.17 s, and 2.20 +/- 0.16 s for the beginners, and 2.03 +/- 0.12 s, 2.03 +/- 0.09 s, and 2.04 +/- 0.1 s for the more experienced players respectively. For the last 20 m of the 30-m sprint, there were differences between the different sprint conditions (P < 0.001) but no differences that were attributable to experience (P = 0.297). The times for the males over the last 20 m without the ball, with the ball under one arm, and with the ball in both hands were 2.58 +/- 0.19 s, 2.61 +/- 0.12 s, and 2.65 +/- 0.12 s for the beginners, and 2.59 +/- 0.12, 2.62 +/- 0.23, and 2.65 +/- 0.18 s for the more experienced players respectively. The times for the females over the last 20 m without the ball, with the ball under one arm, and with the ball in both hands were 3.25 +/- 0.38 s, 3.35 +/- 0.42 s, and 3.40 +/- 0.46 s for the beginners, and 3.04 +/- 0.32 s, 3.06 +/- 0.22 s, and 3.13 +/- 0.27 s for the more experienced players respectively. No gender-specific differences were detected. The results of this study suggest that practising sprints while carrying a ball benefits the early phase of sprinting while carrying the ball.     

大城市的孤单

陌生的城市,全新的环境,孤独的背影……这些熟悉的字眼让太多在外求学的学子感到无限的孤独和寂寥。你是否是其中一员?你的青春期是否也有过这样的漂泊与无助?让我们的外籍专家Brad来回答这份属于青春的迷茫和困惑。     

Am I Scary？

Brad爱旅游,而加国护照的免签国众多,也为他实现旅游梦带来诸多便利。这意味着只要存够足够的钱,他几乎可以去到世界上的任一个地方。但有一个国家,他却是望尘莫及……     

MISSISSIPPI TECH-PREP COORDINATORS: IDENTIFYING CHALLENGES OF THE JOB

ABSTRACT

Mississippi tech-prep coordinators were surveyed to determine their perceptions of the difficulty of their various job responsibilities as identified in the Mississippi Tech Prep Handbook Pilot Site Implementation Guide 1993–94 (1993 Mississippi tech prep handbook pilot site implementation guide 1993-94 . ( 1993 ). Mississippi State , MS : Research and Curriculum Unit for Workforce Development, Vocational and Technical Education . [Google Scholar]). It was hypothesized that their perceptions would be influenced by the number of sites served by individual tech-prep coordinators and the number of years of experience of the individual coordinators. The coordinators' survey also included open-ended questions to gain insight into specific challenges, such as additional duties assigned by the community college, and changes in responsibilities that have occurred over the years. The coordinators were also asked to suggest improvements in their job responsibilities. Further, a separate survey was conducted of the state tech-prep staff members to gain their perspectives of the coordinators' responsibilities. The state staff members were asked to identify what they considered the most difficult duty and the easiest, to suggest improvements to strengthen tech prep, and to name the most important contribution of the coordinators. Challenges for Mississippi tech-prep coordinators were identified in areas of reporting, accountability, the increasing number of sites, and professional development.     

The Compass Rose Effectiveness Model

The effectiveness model focuses the institution on mission achievement through assessment and improvement planning. Eleven mission criteria, measured by key performance indicators, are aligned with the accountability interest of internal and external stakeholders. A Web-based performance assessment application supports the model, documenting the impact of strategic planning on continuous improvement.     

Media representation of the Middle East: constructive student engagement in an online environment

As educators interested in pedagogical uses of technology, we utilize the internet to improve students' knowledge and awareness of the world beyond our own national borders. Web-based technologies offer us resources for our courses and can play an important role in promoting a more active style of learning from our students. Yet when teaching about politically sensitive topics, or regions of the world that are less well known, we inevitably access information that is unfiltered, out-of-context, inaccurate, or biased. This paper will be an exploration of how we taught students to critically engage with each other and with online media sources through a class blog discussing the violence in Gaza during January of 2009. During the two-week project, the students investigated this new media landscape (from blogs to YouTube) increasing their levels of techno-literacy by searching beyond their ‘normal’ sources and by recognizing the political bias present in all online venues. Evidence will show how the students went from passive consumers of networked information to active citizen participants as they expressed their opinions, countered each other's sources, and worked out how to fundamentally disagree without losing civility. The paper will detail the pedagogical practices and challenges to creating online spaces for constructive argumentation about highly volatile issues.     

Effects of total sleep deprivation on endurance cycling performance and heart rate indices used for monitoring athlete readiness

ABSTRACT

This study investigated effects of total sleep deprivation on self-paced endurance performance, and heart rate (HR) indices of athletes' “readiness to perform”. Endurance athletes (n = 13) completed a crossover experiment comprising a normal sleep (NS) and sleep deprivation (SD) condition. Each required completion of an endurance time-trial (TT) on consecutive days (D1, D2) separated by normal sleep or total sleep deprivation. Finishing time, perceived exertion (RPE), mood, psychomotor vigilance (PVT), and HR responses were assessed. Time on D2 of SD was 10% slower than D2 of NS (64 ± 7 vs 59 ± 4 min, P < 0.01), and 11% slower than D1 of SD (58 ± 5 min, P < 0.01). Subjective to objective (RPE:mean HR) intensity ratio was higher on D2 of SD compared with D2 of NS and D1 of SD (P < 0.01). Mood disturbance and PVT mean response time increased on D2 of SD compared with D2 of NS and D1 of SD. Anaerobic threshold and change in TT time were correlated (R = ?0.73, P < 0.01). Sleep helps to optimise endurance performance. Subjective to objective intensity ratios appear sensitive to effects of sleep on athletes’ readiness. Research examining more subtle sleep manipulation is required.