Optimized versus corrected peak power during friction-braked cycle ergometry in males and females

The aim of this study was to compare optimization and correction procedures for the determination of peak power output during friction-loaded cycle ergometry. Ten male and 10 female sports students each performed five 10-s sprints from a stationary start on a Monark 864 basket-loaded ergometer. Resistive loads of 5.0, 6.5, 8.0, 9.5, and 11.0% body weight were administered in a counterbalanced order, with a recovery period of 10 min between sprints. Peak power was greater and occurred earlier, with less work having been done before the attainment of peak power, when the data were corrected to account for the inertial and frictional characteristics of the ergometer. Corrected peak power was independent of resistive load (P > 0.05), whereas uncorrected peak power varied as a quadratic function of load (P < 0.001). For males and females, optimized peak power (971 +/- 122 and 668 +/- 37 W) was lower (P < 0.01) than either the highest (1074 +/- 111 and 754 +/- 56 W respectively) or the mean (1007 +/- 125 and 701 +/- 45 W respectively) of the five values for corrected peak power. Optimized and mean corrected peak power were highly correlated both in males (r = 0.97, P < 0.001) and females (r = 0.96, P < 0.001). The difference between optimized and mean corrected peak power was 37 +/- 30 W in males and 33 +/- 14 W in females, of which approximately 15 W was due to the correction for frictional losses. We conclude that corrected peak power is independent of resistive load in males and females.     

The use of physiological, anthropometric, and skill data to predict selection in a talent-identified junior volleyball squad

The aim of this study was to determine whether physiological, anthropometric, and skill test results could discriminate between junior volleyball players of varying ability. Twenty-eight junior volleyball players competed for selection in a talent-identification volleyball programme. Participants underwent measurements of stature, standing reach stature, body mass, skinfold thickness, overhead medicine ball throw, vertical jump, spike jump, 5-m and 10-m speed, "T" test agility, maximal aerobic power, and passing, setting, serving, and spiking technique and accuracy. A discriminant analysis was conducted on the selected and non-selected groups to obtain a regression equation that could be used to predict selection in junior volleyball squads based on the dependent variables. Passing and serving technique were the only significant variables included in the discriminant analysis. Cross-validation results showed that 17 of 19 selected players (89.5%) and 5 of 9 non-selected players (55.6%) were correctly classified into selected and non-selected groups, respectively, providing an overall predictive accuracy of 78.6%. The results of this study demonstrate that selected skill test results (i.e. subjective coach evaluations of passing technique and serving technique), but not physiological and anthropometric data, discriminate between successful and unsuccessful talent-identified junior volleyball players. These results demonstrate the importance of developing passing and serving technique in talent-identified junior volleyball players.     

大学生体育消费行为决定因素的定量分析——以湖北为例

对学生的体育消费行为进行分类，通过问卷调查的形式，采用统计、计量分析方法，深入分析每类体育消费行为的决定因素及与决定因素之间的定量关系。结果显示，除体育运动的兴趣爱好等主观因素外，学生年生活费用水平、课程压力大小、性别是影响学生体育实物消费的主要客观因素；学生年生活费用水平、性别是影响学生体育信息消费的主要客观因素；学生来源是影响学生体育劳务消费的主要客观因素。这对更深刻地认识体育消费行为、预测高校学生体育消费支出有重要意义。     

青少年足球运动员地域流动性的调查与分析

运用问卷调查法、文献资料法对参加中国足协组织的青少年足球冬训营球员的地域流动性进行了调研。结果表明：现阶段球队招募球员受地理因素的限制越来越小；辽宁省的球员向外流动较多；不同的球员交流目的对本土球员培养的影响作用是不同的；大多数球队都很重视外籍球员在球队中的比例，过低或者过高的比例都不利于球队的发展。旨在为青少年足球人才交流的合理进行、青少年足球运动的可持续发展提供参考。     

Use of dual-task methodology for skill assessment and development: examples from rugby league

We assessed the attentional demands of drawing and passing in rugby league players and investigated the effects of single-task and dual-task training on the acquisition, retention, and transfer of skill in these athletes. In Study 1, high-skilled and lesser-skilled rugby league players performed a standardized 2-on-1 drill under single-task (primary skill in isolation) and dual-task (primary skill while performing a secondary verbal tone recognition task) conditions. No differences were detected in primary task performance between groups, although the performance of the high-skilled players was more resistant to skill decrement under dual-task conditions. In Study 2, high-performance rugby league players were randomly allocated to either a single-task or dual-task training group. Each group underwent 8 weeks of training between the pre- and post-test sessions. While the mean improvement for draw and pass proficiency under dual-task conditions in the dual-task training group was greater than in the single-task training group (10.0% vs. 2.3%), the differences, while providing a moderate effect size (d = 0.57), were not statistically significant. These results suggest that the attentional demands of drawing and passing are reduced in high-skilled rugby league players compared with their lesser-skilled counterparts. In addition, compared with single-task training, dual-task training appears to improve the ability to perform dual-task draw and pass tasks (possibly through an improvement in time-sharing skills). Further studies are required to verify the efficacy of dual-task training as a training stimulus.     

Optimized versus corrected peak power during friction-braked cycle ergometry in males and females

Abstract

The aim of this study was to compare optimization and correction procedures for the determination of peak power output during friction-loaded cycle ergometry. Ten male and 10 female sports students each performed five 10-s sprints from a stationary start on a Monark 864 basket-loaded ergometer. Resistive loads of 5.0, 6.5, 8.0, 9.5, and 11.0% body weight were administered in a counterbalanced order, with a recovery period of 10 min between sprints. Peak power was greater and occurred earlier, with less work having been done before the attainment of peak power, when the data were corrected to account for the inertial and frictional characteristics of the ergometer. Corrected peak power was independent of resistive load (P > 0.05), whereas uncorrected peak power varied as a quadratic function of load (P < 0.001). For males and females, optimized peak power (971 ± 122 and 668 ± 37 W) was lower (P < 0.01) than either the highest (1074 ± 111 and 754 ± 56 W respectively) or the mean (1007 ± 125 and 701 ± 45 W respectively) of the five values for corrected peak power. Optimized and mean corrected peak power were highly correlated both in males (r = 0.97, P < 0.001) and females (r = 0.96, P < 0.001). The difference between optimized and mean corrected peak power was 37 ± 30 W in males and 33 ± 14 W in females, of which approximately 15 W was due to the correction for frictional losses. We conclude that corrected peak power is independent of resistive load in males and females.     

Influence of playing standard on the physical demands of professional rugby league

Abstract

In this paper we report on two studies that investigated the physical demands of professional rugby league match-play. Instudy one, National Rugby League (NRL) and National Youth Competition (NYC) players underwent global positioning system (GPS) analysis during competitive matches. No differences (P > 0.05) were observed between playing standards for minutes played, total distance covered, or the distances covered at low and high speeds. However, NRL players engaged in significantly more repeated high-intensity effort bouts than NYC players (13.1 ± 0.8 bouts vs. 9.7 ± 1.1 bouts). Reductions in physical performance occurred from the first to second half for both NRL and NYC players. In study two, we investigated, in the same players, the physical demands of professional rugby league match-play when players were competing in trial and regular fixture matches. The locomotor demands of trial matches were lower than fixture matches, with players covering less distance per minute of match-play, including less distance at low and high speeds. Players were also less likely to engage in repeated high-intensity effort bouts in trial matches than fixtures. These findings demonstrate that neither NYC matches nor NRL trial matches adequately reflect the intense physical demands of NRL fixture matches.     

初中学生冰上运动安全知识、技能实验干预研究

运用知识讲座、宣传手册、知识竞赛等方式对初一被试学生进行冰上运动安全实验干预,使用自编问卷评估实验前后被试学生冰上运动安全知识技能掌握情况,使用SPSS17．0对获得数据进行自身对照T检验。结果表明：学生通过知识讲座、技能培训、安全手册学习和知识竞赛等干预形式掌握了冰上运动安全知识、安全防护技能和运动损伤急救知识,说明实验干预内容、方法有效可行。     

Exploring the Causal Effect of Interpretation Bias on Attachment Expectations

Attachment theory implies that children's inclination to interpret attachment figures behavior as supportive and available causally influences children's trust in their attachment figure's availability. An experiment was conducted to test whether training children (8–12 years old) to interpret ambiguous interactions with their mothers in a more secure way increases their trust in their mother's availability. Participants (N = 49) were randomly assigned to either a secure condition to train children to interpret their mother's behavior as supportive or a neutral placebo condition, where interpretations were unrelated to maternal support. Results supported the hypothesis: After the secure training, children interpreted maternal behavior more securely and trusted more in her availability. This suggests that attachment‐related processing biases causally affect attachment expectations.     

The invisible impact of educational research

Although there are policy calls for educational research to discover ‘what works’ and thereby inform decision making directly, the research literature argues instead for research to have a ‘conceptual’ impact on practice. Empirical studies also suggest that, when teachers use research, their use is conceptual; research influences the content and the process of their thinking, changing attitudes and perceptions and making educational decision making more intelligent. This study investigates the ways in which educational research has achieved impact on practice from the perspective of the researchers. A sample of highly-rated impact case studies in the UK’s research assessment exercise (REF2014) were subject to content analysis, using qualitative coding techniques. Analysis shows that most research is ‘invisible’ to education practitioners because it is embedded in educational policies, technologies, and services. This ‘invisible use’ is unlikely to realise the conceptual benefits claimed for research utilisation. If educational research is to make educational decision making more intelligent at its point of use, it will be necessary to re-think current notions of quality in research impact.