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921.
Abstract

The purpose of this study was to examine macronutrient intake, energy density and energy intake distribution that may be associated with low energy availability (EA) in Division I female soccer players. The energy intake, exercise energy expenditure and EA of 19 participants (18–21 years) was assessed during the pre-, mid- and postseasons. Repeated measures analysis of variance was performed to examine the changes across the season. Chi-square analysis was performed to examine the distribution of participants meeting the American College of Sports Medicine recommendations for carbohydrate and protein consumption. Independent t-tests were used to compare differences between groups. The proportion of athletes who did not meet the American College of Sports Medicine recommendations for carbohydrate intake (6–10 g . kg–1 BW) was significantly greater in the low (<30 kcal . kg–1 LBM) than higher (≥30 kcal . kg–1 LBM) EA group (χ2 (1) = 7.5; P = 0.006). Participants with low compared to higher EA consumed a lower energy dense dinner (0.8 ± 0.1 vs. 1.4 ± 0.1 kcal . g–1; P = 0.004) after a soccer match during midseason. No differences in the percentage (%) of kilocalories from food (84.5 ± 2.0% vs. 84.7 ± 2.6%), sports drinks (7.3 ± 1.4% vs. 6.0 ± 3.2%), other drinks (7.6 ± 1.5 % vs. 6.0 ± 1.5%) or bars/gels/beans (1.7 ± 0.6 vs. 3.0 ± 1.5) were observed in participants with low compared to higher EA (P > 0.05) during the pre- and midseasons. Identifying inadequate carbohydrate intake and the practice of consuming lower energy dense meals may be important in preventing low EA conditions and consequently the Female Athlete Triad.  相似文献   
922.
Abstract

Although coaches and players recognise the importance of leaders within the team, research on athlete leadership is sparse. The present study expands knowledge of athlete leadership by extending the current leadership classification and exploring the importance of the team captain as formal leader of the team. An online survey was completed by 4,451 participants (31% females and 69% males) within nine different team sports in Flanders (Belgium). Players (N = 3,193) and coaches (N = 1,258) participated on all different levels in their sports. Results revealed that the proposed additional role of motivational leader was perceived as clearly distinct from the already established roles (task, social and external leader). Furthermore, almost half of the participants (44%) did not perceive their captain as the principal leader on any of the four roles. These findings underline the fact that the leadership qualities attributed to the captain as the team’s formal leader are overrated. It can be concluded that leadership is spread throughout the team; informal leaders rather than the captain take the lead, both on and off the field.  相似文献   
923.
Abstract

The aim was to analyse the physical growth and body composition of rhythmic gymnastics athletes relative to their level of somatic maturation. This was a cross-sectional study of 136 athletes on 23 teams from Brazil. Mass, standing height and sitting height were measured. Fat-free and fat masses, body fat percentages and ages of the predicted peak height velocity (PHV) were calculated. The z scores for mass were negative during all ages according to both WHO and Brazilian references, and that for standing height were also negative for all ages according to WHO reference but only until 12 years old according to Brazilian reference. The mean age of the predicted PHV was 12.1 years. The mean mass, standing and sitting heights, body fat percentage, fat-free mass and fat mass increased significantly until 4 to 5 years after the age of the PHV. Menarche was reached in only 26% of these athletes and mean age was 13.2 years. The mass was below the national reference standards, and the standing height was below only for the international reference, but they also had late recovery of mass and standing height during puberty. In conclusion, these athletes had a potential to gain mass and standing height several years after PHV, indicating late maturation.  相似文献   
924.
ABSTRACT

The Female Athlete Triad Coalition (Triad Coalition) and Relative Energy Deficiency in Sport (RED-S) consensus statements each include risk assessment tools to guide athlete eligibility decisions. This study examined how these tools categorized the same set of individuals to an overall risk factor score and qualitatively compared athlete eligibility decisions resulting from each tool. Exercising women (n = 166) with complete screening/baseline datasets from multiple previously conducted studies were assessed. Data used for risk assessment included: anthropometric measurements, dual-energy x-ray absorptiometry scans, exercise and health status surveys, and two disordered eating questionnaires (Three Factor Eating Questionnaire and Eating Disorder Inventory). Individuals were scored on each tool and subsequently categorized as either fully cleared, provisionally cleared, or restricted from play. Based on the Triad Coalition tool, 25.3% of subjects were classified as fully cleared, 62.0% as provisionally cleared, and 12.7% as restricted from play. Based on the RED-S tool, 71.7% of subjects were classified as fully cleared, 18.7% as provisionally cleared, and 9.6% as restricted from play. The Triad Coalition and RED-S tools resulted in different clearance decisions (p < 0.001), with the Triad Coalition tool recommending increased surveillance of a greater number of athletes.  相似文献   
925.
ABSTRACT

Background: Research stemming from Self-Determination Theory (SDT) shows that physical education (PE) teachers who endorse an autonomy-supportive and structuring motivating style positively affect students’ motivation, engagement and learning. Choice provision and positive feedback are two concrete strategies that are part of an autonomy-supportive and structuring style, respectively. While the benefits of choice provision and positive feedback have been shown in contexts other than PE, evidence in the specific context of PE is much scarcer. Grounded in SDT and relying on experimental design, the present study sought to examine the effects of choice provision and positive feedback on students’ motivational experiences in PE, and whether these effects were moderated by students’ actual motor competence (AMC).

Method: A sample of 277 students (41% boys, Mage?=?12.78 years) was randomly assigned to one of four experimental conditions (2?×?2 design). Prior to the experimental manipulation, participants’ AMC was measured with the Test of Gross Motor Development second edition. Participants then watched a videotaped PE lesson, in which the provision of choice (choice – no choice) and type of feedback (corrective feedback – positive and corrective feedback) were manipulated. Participants were asked to imagine how they would feel being a student in the displayed lessons. After watching the video, they completed validated questionnaires on their (1) anticipated need satisfaction and frustration and (2) autonomous and controlled motivation. MANOVAs were conducted to investigate the differences between the experimental groups in terms of anticipated need satisfaction, need frustration and motivation. Multiple linear regression analyses were used to examine the potential moderating role of AMC.

Findings and conclusions: The benefits of choice provision were clearly shown with students in the choice condition anticipating significantly more autonomy, competence and relatedness satisfaction and autonomous motivation, while they anticipated significantly less autonomy and relatedness frustration when compared to students in the no choice condition. Similarly, the addition of positive feedback to corrective feedback yielded clear benefits, with lower averages in anticipated need frustration found among students who watched the videos in which positive feedback was added to corrective feedback. No support was provided for a synergetic motivational effect between choice and positive feedback. Overall, the present findings show the importance of offering choice and providing positive feedback to motivate students in PE, with positive effects being present for all students independent of their initial AMC levels. Although few interaction effects were found, lowly motor competent students benefited even more from receiving positive feedback than highly motor competent students. The findings of this study are important to take into account in PE teacher education programs and professional training programs for PE teachers about how to teach in a (more) motivating way.  相似文献   
926.
927.
An expansion of the eZoomBook (eZB) platform, the ‘myplace4u’ project was designed for place branding and the promotion of literature by linking texts to places—geographical, historical, and touristic places visited physically or imaginatively. The platform allows contributors to collaboratively create and share multi-level books called “eZoomBooks” or digital enriched versions of the original version, organized according to tabs linked to place names in the original. A zooming function enables readers of the eZoomBooks on the platform to navigate freely between the original and enriched versions. Teacher-directed collaboration activities expand the applications of the eZB platform and myplace4u extension.  相似文献   
928.
929.
930.
This study investigated the construction of a spatial model in relation to working memory (WM) and visuospatial abilities. Participants were trained to use either imagery or verbal strategies to process route spatial texts. Results obtained on a free recall task, a verification test and a graphic representation task showed the beneficial effect of using a strategy based on mental images. When imagery strategies were used, a concurrent articulatory task produced interference effects on recall performance, and a spatial tapping task also impaired performance as compared to the control condition. These interference effects suggest that both visuospatial and verbal WM were involved in construction of the spatial model. When repetition strategies were used, however, only the articulatory task produced interference effects, highlighting the role of the verbal WM. To elucidate how the involvement of the visuospatial component may differ in relation to visuospatial abilities, participants with good or poor ability in generation of visual images and spatial manipulation of objects were compared. The benefit of the imagery strategy was found in both groups, but whereas low-visuospatial imagery participants were sensitive to spatial interference, their high ability counterparts were not. These results question the role of imagery processes in the construction of spatial models and their relation to the visuospatial WM.  相似文献   
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