Effects of volleyball match-induced fatigue on knee joint position sense     

Fernando Ribeiro  Fernando Santos  Pedro Gonçalves  José Oliveira 《European Journal of Sport Science》2013,13(6):397-402

Abstract

It has been suggested that a greater number of injuries during the last third of practice sessions or matches could be related to alteration of lower limb neuromuscular control due to neuromuscular fatigue. This fatigue-related effect can be mediated by changes in joint proprioception. In athletes, the use of functional fatigue protocols could have the advantage of mimicking the demands of sporting activity, thus reflecting more specifically the changes in neuromuscular control and proprioception observed in sport settings. The purpose of the present study was to assess the effect of fatigue induced by a volleyball match on knee joint position sense in elite volleyball players. Seventeen female volleyball players aged 18.9±4.2 years from the Portuguese national team volunteered for the study. Knee joint position sense was evaluated by an open kinetic chain technique and active knee positioning, and was reported using absolute, relative, and variable angular errors. Joint position sense measures were obtained before and immediately after a simulated volleyball match of five sets. To ensure that the match was sufficiently intense to induce fatigue, the perceived exertion or exercise intensity was assessed at the end of the match using Borg’ s rating of perceived exertion (RPE) scale. All participants completed the volleyball match (90min duration), reaching or exceeding 15 on the RPE scale (15.59±0.71; range 15–17), equivalent to “hard/heavy work”. After the volleyball match, a significant increase in absolute (2.11°) and relative (1.71°) angular errors was detected. Match-induced fatigue significantly exacerbated the overestimation of the test position. Moreover, the reliability and accuracy in estimating knee angles decreased from rest to the fatigued state, as shown by the increase (264%) in variable error. Our results show that fatigue induced by a volleyball match has a marked effect on knee joint position sense in elite female volleyball players. Knee joint position sense was less accurate and less consistent after the volleyball match. Fatigue induced by a simulated competitive volleyball match resulted in proprioceptive deficits, decreasing sensorimotor system acuity in female volleyball players.  相似文献   

Exploring the uses of mobile phones to support informal learning     

Ieda M. Santos  Nagla Ali 《Education and Information Technologies》2012,17(2):187-203

This paper explores how a group of undergraduate students in the United Arab Emirates (UAE) use their mobile phones to perform informal learning activities related to the content of their courses outside the classroom. The paper also addresses the usefulness of informal learning activities to support students’ learning. The study adopts an exploratory case study design and uses multiple methods of data collection including questionnaires, interviews and diary entries. Main findings suggest that students performed informal learning activities mostly from home, interacting mainly with classmates. It also shows that students were in control of their informal learning activities without teachers’ input. However, it was found that students used only a limited number of applications but these were considered useful to their learning. The paper contributes to a discussion of the implications of training and instructor support to help students to take more advantage of mobile phone applications to support informal learning. Recommendations for further research are discussed.  相似文献   

Near-peer teaching in an anatomy course with a low faculty-to-student ratio     

Durán CE  Bahena EN  Rodríguez Mde L  Baca GJ  Uresti AS  Elizondo-Omaña RE  López SG 《Anatomical sciences education》2012,5(3):171-176

Near-peer teaching is an educational format which utilizes tutors who are more advanced in a curriculum's content to supervise students' activities and to act as instructors in laboratory settings. This format is often used in anatomy laboratory courses. The goal of the present study is to describe the design and implementation of near-peer teaching in an anatomy course and to evaluate students' perceptions of the program. A total of 700 students were registered for this anatomy course which employed near-peer instructors. Of enrolled students, 558 (79.7%) agreed to participate in this study. In general, the practical section (e.g., the clinical hour, image-based anatomy session, and gross anatomy laboratory) of the course was viewed more favorably compared to the theory section (54.8%, n = 306), with dissection and prosection in the laboratory rated as the most valued experiences (34.9%, n = 195). Near-peer teaching is a viable option that satisfies the demands of modern curricula using small groups. This format stimulates learning within courses that have large numbers of students and low faculty-to-student ratios.  相似文献   

国际体育纠纷的种类、国际体育仲裁的特殊性和必要性及解决途径          下载免费PDF全文

Rui Botica Santos 《体育科研》2012,33(6):16-18

摘要：生活中必有冲突,如何解决这些冲突是问题的关键所在。体育纠纷具有特殊性,通过体育共同体以外的方法来解决体育纠纷,可能出现矛盾的裁决、不公平以及法律的不确定性,这些都影响到裁决的有效性、效力和案件裁决的执行。国际体育仲裁院正是基于此背景下建立的,它独立于任何体育组织或地方政府的独立机构。它通过那些适用于体育领域特殊需要的程序规则以仲裁和调解的方式来解决与体育相关的纠纷,也逐渐成为最公正、最有效、最快速、最具成本效益的体育纠纷解决模式。  相似文献   

Isokinetic hamstrings-to-quadriceps peak torque ratio: the influence of sport modality, gender, and angular velocity     

Andrade Mdos S  De Lira CA  Koffes Fde C  Mascarin NC  Benedito-Silva AA  Da Silva AC 《Journal of sports sciences》2012,30(6):547-553

The purpose of this study was to determine differences in hamstrings-to-quadriceps (H/Q) peak torque ratios evaluated at different angular velocities between men and women who participate in judo, handball or soccer. A total of 166 athletes, including 58 judokas (26 females and 32 males), 39 handball players (22 females and 17 males), and 69 soccer players (17 females and 52 males), were evaluated using an isokinetic dynamometer. The H/Q isokinetic peak torque ratios were calculated at angular velocities of 1.05 rad · s?1 and 5.23 rad · s?1. In the analysis by gender, female soccer players produced lower H/Q peak torque ratios at 1.05 rad · s?1 than males involved in the same sport. However, when H/Q peak torque ratio was assessed at 5.23 rad · s?1, there were no significant differences between the sexes. In the analysis by sport, there were no differences among females at 1.05 rad · s?1. In contrast, male soccer players had significantly higher H/Q peak torque ratios than judokas (66 ± 12% vs. 57 ± 14%, respectively). Female handball players produced significantly lower peak torque ratios at 5.23 rad · s?1 than judokas or soccer players, whereas males presented no ratio differences among sports At 5.23 rad · s?1. In the analysis by velocity, women's muscular ratios assessed at 1.05 rad · s?1 were significantly lower than at 5.23 rad · s?1 for all sports; among men, only judokas presented lower ratios at 1.05 rad · s?1 than at 5.23 rad · s?1. The present results suggest that sport modality and angular velocity influence the isokinetic strength profiles of men and women.  相似文献   

3D preserving xviii century barroque masterpiece: Challenges and results on the digital preservation of Aleijadinho's sculpture of the Prophet Joel     

Beatriz Trinchão Andrade  Caroline Mazetto Mendes  Jurandir de Oliveira Santos  Olga Regina Pereira Bellon  Luciano Silva 《Journal of Cultural Heritage》2012,13(2):210-214

We present our recent efforts in the digital preservation of a set of baroque sculptures made by Antônio Francisco Lisboa, known as O. Aleijadinho, which is an important American baroque artist. The set was made in the beginning of the xix century and is composed of 12 near real sized sculptures, hand-carved in soapstone. These sculptures represent 12 of the 16 prophets from the Holy Bible and are part of a UNESCO World Heritage Site. Our group has been collaborating with UNESCO in a project that aims to preserve all these statues. We hereby present our initial efforts, consisting of the 3D digital preservation of the Prophet Joel sculpture. We developed a complete 3D digital preservation pipeline composed of four main stages: data acquisition, 3D reconstruction, texture generation and 3D model visualization. By evaluating our results in this first sculpture, we discuss the improvements we conceived before applying our pipeline in the remaining ones. Finally, we present the 3D model of the Prophet which registers the sculpture's current state and will be used in restoration, research and educational activities. We believe this contribution may be useful to guide further research on similar scenarios, showing how to avoid some practical mistakes and achieve good results.  相似文献   

From the Newspaper to the ‘News‐screen’ in Portuguese Schools     

Maria Manuela Nováis Santos 《Educational Media International》2013,50(1):50-53

Abstracts

English: The paper points out the main objectives of school newspaper production, emphasizing those that may be achieved through work with electronic papers ‐ media competence and hypermedia literacy ‐ which are so important in the Information Society, and crucial for lifelong independent learning which is required in our continuously changing world. A pedagogical approach to the work with online papers which stresses the advantages of ‘learning by doing’ is suggested. A short overview of the Portuguese situation as to the integration of the new Information Technologies in schools will be followed by a presentation of some examples of electronic newspapers produced by Portuguese pupils.

The linear reading mechanisms of traditional papers are compared to those of online papers based on hypertext. The differences in the lay‐out and logic and in the ways of organizing information at the conceptual level will be mentioned, alongside some basic rules for writing an electronic newspaper.  相似文献   

The Contribution of Ethnobiology to the Construction of a Dialogue Between Ways of Knowing: A Case Study in a Brazilian Public High School     

Geilsa Costa Santos Baptista  Charbel Niño El-Hani 《Science & Education》2009,18(3-4):503-520

This paper reports results obtained in pedagogical interventions in a Brazilian public high school which aimed at promoting a dialogue between scientific and traditional knowledge in the context of biology teaching. The interventions were based on the use of a didactic material and teaching sequence elaborated on the grounds of school knowledge about botany, as presented in biology textbooks, and interviews with students who were also farmers, so as to gather data about their ethnobiological knowledge. Our goal was to develop and test resources that can offer support for teachers who wish to build a dialogue between different ways of knowing in multicultural settings. Our results indicate that the use of the didactic material and teaching sequence indeed created possibilities for a dialogue between the students’ ethnobiological knowledge and biology school knowledge. We observed some shortcomings in classroom practice, partly reflecting our very choice of subject matter to develop the teaching sequence. But the interventions also revealed important limitations that we regard as representative of problems that may generally make multicultural science teaching a hard goal to achieve. It was clear that important shortcomings were related to teachers’ difficulties to conduct a dialogue between ways of knowing in a science classroom, and, thus, called attention to the importance of introducing a multicultural dimension into teacher education. We also observed that the fact that students did not show much sensitivity towards dealing with cultural diversity was a factor constraining the success of the interventions. These results highlight the importance of proposing and testing teacher education initiatives aiming at preparing them to teach science in a culturally sensitive manner, and also managing classroom tensions and conflicts so as to make it possible an effective dialogue between different ways of knowing in a multicultural setting.  相似文献   

Physical activity and school recess time: differences between the sexes and the relationship between children's playground physical activity and habitual physical activity   总被引：1，自引：1，他引：0  

Mota J  Silva P  Santos MP  Ribeiro JC  Oliveira J  Duarte JA 《Journal of sports sciences》2005,23(3):269-275

The aims of this study were: (1) to observe participation in moderate-to-vigorous physical activity (MVPA) during school recess periods; (2) to determine the relative importance of physical activity during recesses to overall daily physical activity; and (3) to examine differences in physical activity between the sexes during unstructured recess periods. The participants were 22 school children (10 boys, 12 girls) aged 8 - 10 years (mean = 8.9, s = 0.7) in the third and fourth grades. Daily totals for the physical activity variables were calculated by summing the values for each hour of 14 h of physical activity measurements (08:00 to 22:00 h). Recess times (minutes) were as follows: morning 10:30 to 11:00 h and afternoon 15:30 to 16:00 h. We did not differences between boys and girls in daily total accelerometer counts or the overall time spent in MVPA. However, girls were significantly (P < 0.05) more involved (38%) in MVPA during recess time than boys (31%). Participation in MVPA during recess contributes significantly more (P < 0.05) for girls (19%) than boys (15%) to the total amount of physical activity suggested by international health-related physical activity guidelines, while the percentage of time engaged in MVPA during recess time at school accounts for a small amount of the daily MVPA (6% for boys and 8% for girls). The results of this study suggest that school recess time is an important setting to promote MVPA and contributes to daily physical activity in young children, especially in girls.  相似文献   

Higher Education and Emerging Technologies: Shifting Trends in Student Usage     

Erin Dorris Cassidy  Angela Colmenares  Glenda Jones  Tyler Manolovitz  Lisa Shen  Scott Vieira 《The Journal of Academic Librarianship》2014

This study serves as an update to a previous study by Sam Houston State University librarians about the use and preferences of Internet, communication, and educational technologies among students. Since the previous study was initiated in 2010, the iPad has made its debut and significantly altered the educational technology landscape. In this new landscape, this study investigates student usage of such technologies as instant messaging, cell phones, e-readers, social networking, RSS feeds, podcasts, and tablets. In addition, this study aims to determine which technologies students prefer the library to utilize for a variety of services, such as reference assistance or book renewals, and which technologies may not be worth the investment, such as geosocial networking. The information gained from this survey is intended to provide guidance for libraries looking to provide services utilizing the most popular technologies with the most efficient use of resources. Survey results show an increasing use and dependence on educational technologies and a desire for basic library services to be available on a variety of platforms and technologies.  相似文献