情境领导Ⅱ管理模式在巴西乒乓球队教练训练管理工作中的应用

本研究包含以下几方面内容1.情境领导Ⅱ型模式在巴西乒乓球队训练管理工作中及教练员对运动员的领导关系中的应用情况调查.2.根据运动员的表现,运动员的满意程度,以及教练与运动员之间的相互关系来分析教练员的后续领导行为是否受前阶段管理工作的影响.3.分析运动员的调查结果与相应教练员调查结果的一致性,及其领导管理行为是否为运动队管理多元模式中的一种.研究对象与方法调查对象为61名巴西12～18岁乒乓球运动员和10名乒乓球教练,这些队员和教练均为国家级水平,研究中以运动员满意度问卷形式和运动领导管理标准进行评估.研究结果教练员先前的领导行为影响运动员对教练员的看法,以及运动员的满意程度、教练与运动员相互之间的关系等.那些运动成绩较好的、经验相对丰富的、教练监督指导得比较多的运动员,他们的问卷答案与教练员的问卷结果有很高的一致性.对教练员的训练教导工作和民主行为方面,男子运动员的答案要比女子运动员表现出较高的一致性.女运动员对教练员的个别对待方式与民主行为表现出较好的满意度.运动员的问卷结果与相应教练员的调查结果的一致性在很大程度上依赖于训练过程中产生的良好效果与运动员的满意度,这反映了多元领导模式的规则.另外,虽然我们的研究并没有很好地验证情境领导Ⅱ模式在运动队训练管理中的应用情况,但是,调查分析结果表明了合适的多元领导模式在运动队训练工作中进行有效领导的重要性.这些结果也说明在多元领导模式的基础上,采用足够合理的方法是检验情境领导Ⅱ模式在运动训练管理中应用情况的关键.     

Effects of replica running shoes upon external forces and muscle activity during running

Twelve participants ran (9 km · h(-1)) to test two types of running shoes: replica and original shoes. Ground reaction force, plantar pressure and electromyographic activity were recorded. The shoes were tested randomly and on different days. Comparisons between the two experimental conditions were made by analysis of variance (ANOVA) test (P ≤ 0.05). The time to first peak, loading rate of the first peak and impulse of the first 75 ms of stance were significantly different between the shoes (P ≤ 0.05), revealing an increase of impact forces for the replica shoes. The peak plantar pressure values were significantly higher (P ≤ 0.05) when wearing replica shoes. During running, the contact area was significantly smaller (P ≤ 0.05) for the replica shoe. The electromyographic activity of the analysed muscles did not show changes between the two shoes in running. These findings suggest that the use of replica running shoes can increase the external load applied to the human body, but may not change the muscle activity pattern during locomotion. This new mechanical situation may increase the risk of injuries in these movements.     

Validity and reliability of a new field test (Carminatti's test) for soccer players compared with laboratory-based measures

The aim of this study was to assess the validity (Study 1) and reliability (Study 2) of a novel intermittent running test (Carminatti's test) for physiological assessment of soccer players. In Study 1, 28 players performed Carminatti's test, a repeated sprint ability test, and an intermittent treadmill test. In Study 2, 24 players performed Carminatti's test twice within 72 h to determine test-retest reliability. Carminatti's test required the participants to complete repeated bouts of 5 × 12 s shuttle running at progressively faster speeds until volitional exhaustion. The 12 s bouts were separated by 6 s recovery periods, making each stage 90 s in duration. The initial running distance was set at 15 m and was increased by 1 m at each stage (90 s). The repeated sprint ability test required the participants to perform 7 × 34.2 m maximal effort sprints separated by 25 s recovery. During the intermittent treadmill test, the initial velocity of 9.0 km · h(-1) was increased by 1.2 km · h(-1) every 3 min until volitional exhaustion. No significant difference (P > 0.05) was observed between Carminatti's test peak running velocity and speed at VO(2max) (v-VO(2max)). Peak running velocity in Carminatti's test was strongly correlated with v-VO(2max) (r = 0.74, P < 0.01), and highly associated with velocity at the onset of blood lactate accumulation (r = 0.63, P < 0.01). Mean sprint time was strongly associated with peak running velocity in Carminatti's test (r = -0.71, P < 0.01). The intraclass correlation was 0.94 with a coefficient of variation of 1.4%. In conclusion, Carminatti's test appears to be avalid and reliable measure of physical fitness and of the ability to perform intermittent high-intensity exercise in soccer players.     

The peak velocity derived from the Carminatti Test is related to physical match performance in young soccer players

ABSTRACT

The aim of this study was to examine the relationship between the peak velocity derived from the Carminatti Test (T-CAR) (PV_T-CAR) and physical match performance in young soccer players. Thirty-three youth soccer players were recruited from 2 non-professional clubs. Friendly matches and small-sided game were performed. Physical match demands were assessed using Global Positioning System (GPS) technology. On a separate occasion, the players were submitted to the T-CAR. Players were categorised into 3 groups based on their T-CAR performance: Low (PV_T-CAR ≤ P33), Intermediate (P33 > PV_T-CAR < P66) and High (PV_T-CAR ≥ P66). The PV_T-CAR (15.5 ± 0.7 km·h^?1) was significantly related to high-intensity activities (HIA; r = 0.78, P < 0.001), high-intensity running (HIR; r = 0.66, P < 0.001), sprinting (r = 0.62, P < 0.001) and total distance (TD) covered (r = 0.47, P < 0.01) during friendly matches. The PV_T-CAR was strongly correlated with the amount of HIA (r = 0.81, P < 0.001), HIR (r = 0.85, P < 0.001) and TD covered (r = 0.81, P < 0.001) during small-sided game. No significant correlation was observed between the PV_T-CAR and distance of sprinting (r = 0.49, P = 0.067) during small-side game. Furthermore, players in the High group covered significantly more TD (10%) and did more HIA (42%), sprinting (31%) and HIR (25%) during friendly matches compared to the players classified as having Low performance on the T-CAR. These differences still remained after adjusting for chronological age (CA), maturity and body size. In conclusion, the current study gives empirical support to the ecological and construct validity of this novel field test (T-CAR) as an indicator of match-related physical performance in young soccer players during pubertal years.     

Be(com)ing an excellent student: a qualitative study with engineering undergraduates

This study explores the factors affecting the development of academic excellence on a group of 33 high-achieving engineering students. Participants were interviewed individually to explore several personal and contextual aspects of their past and current academic pathways. The results obtained reflect three main contributions to the conceptualization and understanding of excellence in academic contexts: the need to adopt a multidimensional and dynamic view about the concept of excellence; the existence of a variety of possible pathways and environmental conditions to achieve excellence; and the understanding of excellence as a process undergoing continuous development, which thrives within the family context and school environment, and that seems to be continuously nurtured by individuals in interaction with their contexts.     

Validity and reliability of a new field test (Carminatti's test) for soccer players compared with laboratory-based measures

Abstract

The aim of this study was to assess the validity (Study 1) and reliability (Study 2) of a novel intermittent running test (Carminatti's test) for physiological assessment of soccer players. In Study 1, 28 players performed Carminatti's test, a repeated sprint ability test, and an intermittent treadmill test. In Study 2, 24 players performed Carminatti's test twice within 72 h to determine test–retest reliability. Carminatti's test required the participants to complete repeated bouts of 5 × 12 s shuttle running at progressively faster speeds until volitional exhaustion. The 12 s bouts were separated by 6 s recovery periods, making each stage 90 s in duration. The initial running distance was set at 15 m and was increased by 1 m at each stage (90 s). The repeated sprint ability test required the participants to perform 7 × 34.2 m maximal effort sprints separated by 25 s recovery. During the intermittent treadmill test, the initial velocity of 9.0 km · h^?1 was increased by 1.2 km · h^?1 every 3 min until volitional exhaustion. No significant difference (P > 0.05) was observed between Carminatti's test peak running velocity and speed at VO_2max (v-VO_2max). Peak running velocity in Carminatti's test was strongly correlated with v-VO_2max (r = 0.74, P < 0.01), and highly associated with velocity at the onset of blood lactate accumulation (r = 0.63, P < 0.01). Mean sprint time was strongly associated with peak running velocity in Carminatti's test (r = ?0.71, P < 0.01). The intraclass correlation was 0.94 with a coefficient of variation of 1.4%. In conclusion, Carminatti's test appears to be avalid and reliable measure of physical fitness and of the ability to perform intermittent high-intensity exercise in soccer players.     

Use of the “Tree” Analogy in Evolution Teaching by Biology Teachers

This work discusses the use of Darwin’s ‘Tree of Life’ as a didactic analogy and metaphor in teaching evolution. It investigates whether biology teachers of pupils from 17 to 18 years old know Darwin’s text ‘Tree of Life’. In addition, it examines whether those teachers systematically employ either the analogies present in that text or other analogies between the tree and evolution, and whether they adopt a specific methodology for teaching with analogies and metaphors (A&M). The academic training of teachers regarding use of A&M is review briefly. A diagnostic study was carried out with biology teachers in a public school in the town of Contagem in the state of Minas Gerais in Brazil. The data were obtained through direct observation, questionnaires and a focus group. The teachers pointed out in the questionnaires that some details of Darwin’s analogy are utilized as a resource. However, analysis of the data indicates that the ‘Tree of Life’ text is not known or utilized in class. At the same time, the teachers state that they use aspects of the tree as a didactic resource to teach evolution and that its use facilitates the learning of content. The teachers have little knowledge of specific methodologies of teaching with analogies and metaphors, revealing that their training is incomplete in this area.     

The issue of the arrangement of new environments for science education through collaborative actions between schools,museums and science centres in the Brazilian context of teacher training

We present, in this article, an investigation about the potential of the relationship between formal and non-formal educational environments. Therefore it is not an empirical research, but an essay on the topic. This paper demonstrates the concept that science education and science outreach can be privileged by actions that are developed by closer relations between formal and non-formal places. Currently, non-formal environments such as museums and science and technology centres are considered potential educational resources within the reach of schools. Educators from museums have conducted studies which demonstrate a predominant model of the utilization of these institutions by teachers, which consists of illustrative visits during the exhibitions, but does not feature a collaborative relationship or partnership between schools and these institutions. In Brazil, the main examples of approaches to collaboration between these places and schools have been taking place through the initiatives of teachers or through projects developed by the educational sector, aiming to broaden the dialogue between their institutions and the school community. Another approach mechanism relates to research and extension projects developed by university researchers, sponsored by state and federal funding agencies. In this case, the universities and university museums appear as new social actors that stand in the way of the schools and the cultural environments, complicating the relationship and, at the same time, bringing new questions to the field of educational research. We believe that the discourse in this paper should bring about further discussions in the initial teacher training courses to contribute to the understanding of practices related to the extension of the field of activity of the school.