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161.
Danielle M. Logue Sharon M. Madigan Mirjam Heinen Sarah-Jane McDonnell Eamonn Delahunt Clare A. Corish 《European Journal of Sport Science》2019,19(1):112-122
ABSTRACTIntroduction: Low energy availability (LEA) results in physiological adaptations, which can contribute to unfavourable health outcomes. Little information exists on risk of LEA in active individuals competing in different sports or levels of competition. The aims of this study were to (1) identify risk of LEA in females competing at different levels of competition and (2) investigate associations between risk of LEA, illness and dietary habits. Methods: The validated questionnaire, ‘Low Energy Availability in Females Questionnaire’ was distributed online (November 2016–February 2017) to assess risk of LEA. Twenty-nine additional questions collected information on demographics, illness history and dietary habits. Participants were considered at risk of LEA if they attained a score of?≥?8 and were grouped into: (i) international; (ii) provincial/inter-county; (iii) competitive; and (iv) recreationally active. Chi-square and logistic regression analyses were used to explore differences between those at risk or not at risk of LEA. Results: Risk of LEA was identified in 40% (n?=?331) of 833 participants and was 1.7 and 1.8 times more likely in international and provincial/inter-county athletes compared to those who were recreationally active (International: odds ratios (OR) 1.68, 95% confidence intervals (95%CI) 1.12–2.54; Provincial/inter-county: OR 1.83, 95%CI 1.20–2.77). In participants at risk of LEA, missing >22 days of training during the previous year due to illness occurred 3 times more frequently (OR 3.01, 95%CI 1.81–5.02). Conclusion: Risk of LEA was widespread in this heterogeneous sample. Awareness of LEA and the development of appropriate energy management strategies to ensure athlete health across levels of competition are required. 相似文献
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164.
K. S. Yakovlev D. A. Makarov E. S. Baskin 《Scientific and Technical Information Processing》2015,42(5):347-358
In the article we solve path planning task for an agent being multirotor unmanned aerial vehicle (multicopter). We propose an approach of estimating path geometry constraints based on UAV flight dynamics model and control constraints. Than we introduce a new path finding method which takes into consideration those geometry constraints and study this method both theoretically and empirically. 相似文献
166.
Michael A. Peters 《Educational Philosophy and Theory》2020,52(8):805-810
167.
Chris Bishop Lucas A. Pereira Valter P. Reis Paul Read Anthony N. Turner Irineu Loturco 《Journal of sports sciences》2020,38(11-12):1296-1303
ABSTRACT The aims of the present study were to provide an in-depth comparison of inter-limb asymmetry and determine how consistently asymmetry favours the same limb during different vertical jump tests. Eighteen elite female under-17 soccer players conducted unilateral squat jumps (SJ), countermovement jumps (CMJ) and drop jumps (DJ) on a portable force platform, with jump height, peak force, concentric impulse and peak power as common metrics across tests. For the magnitude of asymmetry, concentric impulse was significantly greater during the SJ test compared to CMJ (p = 0.019) and DJ (p = 0.003). No other significant differences in magnitude were present. For the direction of asymmetry, Kappa coefficients revealed fair to substantial levels of agreement between the SJ and CMJ (Kappa = 0.35 to 0.61) tests, but only slight to fair levels of agreement between the SJ and DJ (Kappa = ?0.26 to 0.18) and CMJ and DJ (Kappa = ?0.13 to 0.26) tests. These results highlight that the mean asymmetry value may be a poor indicator of true variability of between-limb differences in healthy athletes. The direction of asymmetry may provide a useful monitoring tool for practitioners in healthy athletes, when no obvious between-limb deficit exists. 相似文献
168.
Leonardo S. Fortes Dalton De Lima-Junior Lenamar Fiorese José R. A. Nascimento-Júnior Arnaldo L. Mortatti Maria E. C. Ferreira 《Journal of sports sciences》2020,38(5):552-558
ABSTRACTThe objective of this study was to analyse the effect of the use of social networks in smartphones or playing video games on the passing decision-making performance in professional soccer athletes. Participants were 25 male professional soccer athletes (mean ± SD: age 23.4 ± 2.8 years). The participants performed three randomised conditions divided into three groups: control (CON), smartphone (SMA), and video game (VID). Before and after each experimental condition, the Stroop Task assessed the level of induced mental fatigue. Then, the athletes performed a simulated soccer match. A CANON® camera recorded the matches for further analysis on passing decision-making performance. A group effect was identified (p < .01) with impairment on passing decision-making performance for the SMA (p = .01, ES = 0.5) and VID (p = .01, ES = 0.5) conditions. We concluded that the use of social networks on smartphones and/or playing video games right before official soccer matches might impair the passing decision-making performance in professional soccer athletes. 相似文献
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170.
Jean B. Schumaker Joseph B. Fisher Lisa D. Walsh Paula E. Lancaster 《Learning disabilities research & practice》2020,35(4):180-200
In each of two studies, teachers were randomly assigned to either a Virtual Workshop (VW) group that used a computerized professional development program or an Actual Workshop (AW) group that participated in face-to-face professional development, including discussion, feedback, and collaboration. In both studies, teachers’ posttest scores related to their knowledge of the Question Exploration Routine and their plans for using it were significantly higher than their pretest scores. In Study 2, both groups’ posttest scores with regard to implementation and planning of the routine were significantly greater than their pretest scores. There were no significant differences between the groups at posttesting on any measure. The posttest knowledge scores of the whole groups of students and the subgroups of students with LD being taught by both groups of teachers were significantly higher than their pretest scores. All teachers indicated that they were satisfied with the training and the routine. VW teachers in both studies indicated that they were satisfied with the software program. 相似文献