Effect of surrogate design on the measured stiffness of snowboarding wrist protectors     

Caroline Adams  David James  Terry Senior  Tom Allen  Nick Hamilton 《Sports Engineering》2018,21(3):217-225

In snowboarding, the wrist is the most common injury site, as snowboarders often put their arms out to cushion a fall. This can result in a compressive load through the carpals coupled with wrist hyperextension, leading to ligament sprains or carpal and forearm bone fractures. Wrist protectors are worn by snowboarders in an effort to reduce injury risk, by decreasing peak impact forces and limiting wrist extension to prevent hyperextension during falls. There is no international standard or universally accepted performance specification that snowboarding wrist protectors should conform to, resulting in an inability to judge which designs offer the best protection. This study investigated how surrogate arm design affected the stiffness of wrist protectors during quasi-static mechanical testing. Three surrogate arms with increasing design complexity were used to test three wrist protectors. The results show that surrogate design does influence the stiffness of snowboarding wrist protectors. Given that the surrogate does influence protector performance, it is recommended that a standard surrogate design is established for research and product testing.  相似文献   

排名前10的与预防运动和体育活动猝死相关的关键问题          下载免费PDF全文

Rachel K. Katch  Samantha E. Scarneo  William M. Adams  Lawrence E. Armstrong  Luke N. Belval  Julie M. Stamm  Douglas J. Cas  朱为模审校 《体育科研》2018,(2):31-46

参加有组织的体育运动和休闲活动存在发生严重伤病甚至死亡的内在风险。虽然造成体育运动或体育活动中猝死的原因有很多,但运动医学和循证标准治疗方面的进展已使临床医生得以更有效地预防、发现和治疗可能致死的伤患。随着研究与技术不断发展进步,当前的治疗标准正在不断发展以更好地改善患者的治疗效果。本文提出了10个与运动和体育活动中猝死的主要原因及其治疗手段有关的关键问题,未来开展的研究将提高运动员和休闲运动爱好者参与运动的安全度。当前证据表明,如采取正确的预防策略或最佳治疗方案,绝大多数的死亡案例是可以避免的。  相似文献   

Examining the capacity of a sport for development programme to create social capital     

Andrew Adams  Kevin Harris  Iain Lindsey 《Sport in Society》2018,21(3):558-573

Robert Putnam’s conceptualization of social capital has been commonly associated with, and used to analyse, sport-for-development programmes. This paper bucks this trend and uses James Coleman’s rational strain of social capital to examine the use of sport as a component part of a programme to support male adults in addressing connected problems of substance misuse, homelessness and other forms of social exclusion. Using a qualitative research strategy, in-depth and longitudinal data were collected using individual interviews and focus groups with programme participants and key stakeholders over a three-year period. The results suggest the importance of unintentionality for the formation and use value of social capital; indicating that social capital created through this programme was individual, contingent on interactional context and benefited individuals in line with Coleman’s six aspects of social capital.  相似文献   

Effect of a randomised 12-week resistance training programme on muscular strength,cross-sectional area and muscle quality in women having undergone Roux-en-Y gastric bypass     

Paul Daniels  Timothy A. Brusseau  Morgan S. Hall  Lance Davidson  Ted D. Adams 《Journal of sports sciences》2018,36(5):529-535

The purpose of this study was to examine the effect of a 12-week resistance training programme on fat-free mass (FFM), muscle cross-sectional area, muscular strength and muscle quality in women who underwent Roux-en-Y gastric bypass surgery. Participants were 16 women (mean age = 44.9 ± 10.2 years) from bariatric surgical groups who were randomly assigned into either a control or an intervention group. Air displacement plethysmography measured FFM and magnetic resonance imaging measured quadriceps muscle cross-sectional area and whole thigh muscle cross-sectional area. Muscular strength and quality was assessed using an estimated 1-Repetition Maximum assessment. All measurements were collected twice, at baseline and at a 12-week follow-up. There were significantly greater improvements in leg press strength (mean differences = 55.4%, P < 0.001, Cohen’s d = 2.4), leg extension strength (mean differences = 18.0%, P = 0.014, Cohen’s d = 0.86) and leg press muscle quality (mean differences = 54.5%, P < 0.001, Cohen’s d = 1.9) in the intervention group compared to the control group following the resistance training programme. The resistance training intervention significantly improved muscular strength and quality; however, it did not illicit changes in FFM or muscle cross-sectional area in women who underwent Roux-en-Y gastric bypass surgery.  相似文献   

Premiums,announcement returns and desperation in high tech mergers: A growth options analysis     

Sean M. Davis  Jeff Madura 《The Journal of High Technology Management Research》2017,28(1):61-78

We examine the announcements of high tech mergers using a relatively new proxy for growth options we call “growth to book.” We find this adds significantly to help explain the premiums paid and announcement period abnormal returns when acquiring tech targets. Higher synergies are expected by managers and investors when targets have low growth options and acquirers have high growth options, resulting in higher premiums paid and either less negative or more positive abnormal returns. However, we find significant variation in the results by the relative size of the target and when low growth to book (GTB) firms acquire. While high GTB acquirers tend to pay more in premiums, low GTB acquirers can pay higher premiums and receive some of the most negative returns at announcement. We find evidence some acquisitions are motivated by desperation as these acquirers have the lowest GTB and do a disproportionate number of the relatively largest deals, receiving the worst abnormal returns at announcement.  相似文献   

Batting last as a home advantage factor in men's NCAA tournament baseball     

Steven R Bray  Jeff Obara  Matt Kwan 《Journal of sports sciences》2013,31(7):681-686

In baseball and softball, there is a rule that allows the home team to have the last at-bat and thus the final opportunity to win the game. However, in tournament play, this rule is often set aside and, instead, batting order is decided by other means (e.g. tournament rules, the flip of a coin). The purpose of this study was to examine the impact of the batting last rule on game outcome in NCAA men's regional tournament baseball. It was hypothesized that host (i.e. home) teams would win a greater percentage of the games in which they batted last compared with when they batted first. This hypothesis was not supported. Closer examination of the last inning of play showed home teams were no more likely to have won the game during their last bat than visitors playing other visitors. The results suggest that the batting last rule contributes minimally, if at all, to home advantage in NCAA tournament baseball.  相似文献   

Throwing performance in water polo is related to in-water shoulder proprioception     

Andrea H. Hams  Kerrie Evans  Roger Adams  Gordon Waddington  Jeremy Witchalls 《Journal of sports sciences》2013,31(22):2588-2595

ABSTRACT

Water polo players require a high level of upper-extremity strength, flexibility and coordination to achieve a peak level of throwing performance. Increased levels of shoulder proprioceptive acuity, strength and range of motion (ROM) have been previously associated with higher sporting performance. A coach-rating scale, used to quantify an athlete’s kicking proficiency in soccer; was adapted in the current study to measure each coach’s subjective expert opinion regarding athletes’ throwing mechanics, velocity, and accuracy. To examine this hypothesis shoulder proprioception acuity of 18 water polo players was measured both in-water and on-land using an AMEDA apparatus and correlated with coach-rated throwing performance and clinical measures of shoulder strength and ROM. There was a moderate positive correlation between the in-water and the on-land proprioception acuity (r = 0.47, p < 0.05). The in-water score showing a strong positive correlation with coach rated throwing mechanics (r = 0.68, p < 0.05) and velocity (r = 0.75, p = 0.02), suggesting that superior proprioception acuity contributed to fast, mechanically-efficient throwing. These findings support the notion that in-water proprioceptive acuity is an important determinant of the throwing performance achieved by water polo athletes and its measurement may be a valuable adjunct to current athlete screening.  相似文献   

Response to a Cold Pressor Test during Physical Training     

Ernest D. Michael Jr.  Arthur Gallon  Adran Adams 《Research quarterly for exercise and sport》2013,84(3):382-388

Abstract

Members of the 1958–59 varsity basketball team at Santa Barbara and a control group of physical education majors not in training were tested each three weeks during a 17-week season of basketball competition on their response to a step test and to a cold pressor test. The results indicated that significant step test recovery pulse rate changes were made by the basketball players after three weeks of training. Maximum changes were found to occur after 17 weeks of training. The diastolic pressure response to the cold pressor test increased significantly (7 mmHg.) after six weeks of training and this was maintained for 17 weeks. The results indicated that a possible increased sensitivity or tone of the peripheral vessels resulted from physical training.  相似文献   

Student participation styles in adventure education     

Mark H. Zmudy  Matthew D. Curtner-Smith  Jeff Steffen 《Sport, Education and Society》2013,18(4):465-480

Sport pedagogy researchers have contributed much to the literature on physical education teaching by describing the participation styles of children, youth and young adults in various settings. The purpose of this study was to describe the participation styles of children enrolled in two consecutive week-long summer adventure camps. Primary participants were 31 elementary and middle school students. Secondary participants were the two adventure educators (AEs) responsible for carrying out all the instruction at the camps. Data were collected using a variety of qualitative techniques and analysed using standard interpretive methods. Nine participation styles were identified indicating that the children in the camps had differing experiences of adventure education and varying degrees of success. Some of the participation styles had similar characteristics to those discovered previously in middle school physical education. Despite these similarities and unlike the middle school setting, there was no indication that a hierarchy of participation styles existed and, consequently, there was no sign of any bullying. Reasons for this difference may well have been the heavy focus on affective objectives within adventure education, much lower student–teacher ratios, higher levels of supervision and management, and greater instructional intent and skill.  相似文献   

Teachers’ perceptions of assessments of their mathematical knowledge in a professional development course     

Michelle T. Chamberlin  Jeff D. Farmer  Jodie D. Novak 《Journal of Mathematics Teacher Education》2008,11(6):435-457

The purpose of the project reported in this article was to evaluate how assessing teachers’ mathematical knowledge within a professional development course impacted from the teachers’ perspective their learning and their experience with the course. The professional development course consisted of a 2-week summer institute and the content focus was geometry. We had decided to assess the mathematical learning of the teachers during this professional development course for various accountability reasons, but were concerned about possible negative by-products of this decision on the teachers and their participation. Thus, we worked to design assessment in ways that we hoped would minimize negative impacts and maintain a supportive learning environment. In addition, we undertook this evaluation to examine the impacts of the assessment, which included homework, quizzes, various projects, and an examination for program evaluation. Seventeen grade 5–9 teachers enrolled in the course participated in the study by completing written reflections and by describing their experiences in interviews. We learned that while our original intent was “to do no harm,” the teachers reported that their learning was enhanced by the assessment. The article concludes by describing the various properties of the assessments that the teachers identified as contributing to their learning of the geometry content, many of which align with current recommendations for assessing and evaluating grade K-16 mathematics students.

Michelle T. ChamberlinEmail:

  相似文献