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151.
M Martín-Matillas FB Ortega JR Ruiz D Martínez-Gómez G Vicente-Rodríguez A Marcos L Béghin A Kafatos M González-Gross M Zaccaria D Molnár S De Henauw M Sjöström LA Moreno MJ Castillo On Behalf Of The Helena Study 《Journal of sports sciences》2012,30(13):1329-1335
Abstract High physical fitness in childhood and adolescence is positively associated with favourable health-related outcomes. Our aim was to examine the relationship between relatives' (father, mother, brother, sister, and best friend) physical activity engagement and encouragement on adolescents' physical fitness. Adolescents were part of the HELENA study, a multi-centre study conducted in 10 cities from nine European countries in 2006-2008. Participants were 3288 adolescents (48% boys, 52% girls) aged 12.5-17.5 years with valid data on at least one of the three fitness variables studied: muscular strength (standing long jump), speed/agility (4×10 m shuttle run), and cardiorespiratory fitness (20 m shuttle run). The adolescents reported their relatives' physical activity engagement and encouragement. Analysis of covariance showed that relatives' physical activity engagement (father, mother, brother, and best friend) was positively related to cardiorespiratory fitness (P?0.05); and mother's and sisters' physical activity engagement were positively associated with higher muscular strength in adolescents (P?0.05). Furthermore, father's physical activity encouragement was positively linked to physical fitness (all fitness components) in adolescents (P?0.05). Interventions aimed at improving physical fitness in young people might be more successful when family members, particularly mothers and fathers, are encouraged to engage in physical activity and support adolescents' physical activity. 相似文献
152.
This study examined the influence of the regression model and initial intensity of an incremental test on the relationship between the lactate threshold estimated by the maximal-deviation method and the endurance performance. Sixteen non-competitive, recreational female runners performed a discontinuous incremental treadmill test. The initial speed was set at 7 km · h?1, and increased every 3 min by 1 km · h?1 with a 30-s rest between the stages used for earlobe capillary blood sample collection. Lactate-speed data were fitted by an exponential-plus-constant and a third-order polynomial equation. The lactate threshold was determined for both regression equations, using all the coordinates, excluding the first and excluding the first and second initial points. Mean speed of a 10-km road race was the performance index (3.04 ± 0.22 m · s?1). The exponentially-derived lactate threshold had a higher correlation (0.98 ≤ r ≤ 0.99) and smaller standard error of estimate (SEE) (0.04 ≤ SEE ≤ 0.05 m · s?1) with performance than the polynomially-derived equivalent (0.83 ≤ r ≤ 0.89; 0.10 ≤ SEE ≤ 0.13 m · s?1). The exponential lactate threshold was greater than the polynomial equivalent (P < 0.05). The results suggest that the exponential lactate threshold is a valid performance index that is independent of the initial intensity of the incremental test and better than the polynomial equivalent. 相似文献
153.
Enrique Herrera-Viedma Guy De Tré Slawomir Zadrozny Jose Angel Olivas 《Information processing & management》2012
Soft Computing (SC) tools present a great potential in real-life problems related with engineering, industrial applications, medicine, finances, etc. In this special issue we present a set of seven papers that report original research about the use of SC techniques to solve the problems in the field of information access on the Web. 相似文献
154.
Schmitt KU Wider D Michel FI Brügger O Gerber H Denoth J 《Sports biomechanics / International Society of Biomechanics in Sports》2012,11(1):57-72
Wrist injuries are frequently observed after falls in snowboarding. In this study, laboratory experiments mimicking forward and backward falls were analysed. In six different falling scenarios, participants self-initiated falls from a static initial position. Eighteen volunteers conducted a total of 741 trials. Measurements were taken for basic parameters describing the kinematics as well as the biomechanical loading during impact, such as impact force, impact acceleration, and velocity. The effective mass affecting the wrist in a fall also was determined. The elbow angle at impact showed a more extended arm in backward falls compared to forward falls, whereas the wrist angle at impact remained similar in forward and backward falls. The study results suggest a new performance standard for wrist guards, indicating the following parameters to characterize an impact: an effective mass acting on one wrist of 3-5 kg, an impact angle of 75 degrees of the forearm relative to the ground, and an impact velocity of 3 m/s. 相似文献
155.
In two experiments, we examined how preexposure to discriminative stimuli and introduction of a 21-day retention interval
affected the latent inhibition (LI) and perceptual learning (PL) of rats in a choice-maze discrimination task. Experimental
groups were preexposed to three wall patterns, one in each of three arms of a maze. Control groups were preexposed only to
white arms. PL groups were trained to discriminate A versus B, and LI groups, to discriminate A or B versus C. The A and B
patterns shared many elements not shared with the C pattern. In Experiment 1, both at the end of training and after the subsequent
retention interval, the PL groups performed better than controls, whereas the LI groups performed worse. In Experiment 2,
inserting the 21-day retention interval between preexposure and discrimination training disrupted final measures of LI but
not PL performance. Implications for current concepts of PL and LI are discussed. 相似文献
156.
Attempting to push early modern presentism to the radical, logical conclusion of a more personal historicism, this essay draws on a number of interpretive practices and theoretical insights – Stephen Greenblatt’s self-reflectivity, Toni Morrison’s ‘rememory’, Marianne Hirsch’s ‘postmemory’, bell hooks’s ‘passion of experience’, and Linda Charnes’s alternative historicism – to establish the ethical and interpretive significance of my own painful situatedness as an African American man in Renaissance/Early Modern studies. Specifically, I illustrate that significance in a reading of Richard Mulcaster’s Positions Concerning the Bringing Up of Children, a sixteenth-century educational treatise that responds, as I argue, to early modern educational access and social mobility with an insidiously complex, exclusionary admissions policy. 相似文献
157.
As secondary students’ interest in science is decreasing, schools are faced with the challenging task of providing adequate instruction to engage students—and more particularly the disadvantaged students—to learn science and improve their science inquiry skills. In this respect, the integration of Web-based collaborative inquiry can be seen as a possible answer. However, the differential effects of Web-based inquiry on disadvantaged students have barely been studied. To bridge this gap, this study deals with the implementation of a Web-based inquiry project in 19 secondary classes and focuses specifically on gender, achievement level, and academic track. Multilevel analysis was applied to uncover the effects on knowledge acquisition, inquiry skills, and interest in science. The study provides quantitative evidence not only that a Web-based collaborative inquiry project is an effective approach for science learning, but that this approach can also offer advantages for students who are not typically successful in science or who are not enrolled in a science track. This approach can contribute to narrowing the gap between boys and girls in science and can give low-achieving students and general-track students an opportunity to develop confidence and skills for learning science, bringing them to a performance level that is closer to that of high-achieving students. 相似文献
158.
159.
Julio Guerra Margarita Ortiz-Rojas Miguel Angel Zúñiga-Prieto Eliana Scheihing Alberto Jiménez Tom Broos Tinne De Laet Katrien Verbert 《British journal of educational technology : journal of the Council for Educational Technology》2020,51(4):973-1001
Despite the success of academic advising dashboards in several higher educational institutions (HEI), these dashboards are still under-explored in Latin American HEI's. To close this gap, three different Latin American universities adapted an existing advising dashboard, originally deployed at the KU Leuven to their own context. In all three cases, the context was the main ruling factor to these adaptations. In this paper, we describe these adaptions using a framework that focuses on four different elements of the context: Objectives, Stakeholders, Key moment and Interactions. Evaluation of the adapted dashboards in the three different Latin American universities is conducted through pilots. This evaluation shows the value of the dashboard approach in different contexts in terms of satisfaction, usefulness and impact in academic decision-making and advising tasks. The main contribution of this paper is the systematic reporting of the adaptations to an academic advising dashboard and showing the value of an academic advising dashboard on academic decision-making and advising tasks. 相似文献
160.
Great Expectations? Childhood,Family, and Middle-Class Social Mobility in Nineteenth-Century England
Christina De Bellaigue 《Cultural and Social History》2019,16(1):29-46
ABSTRACTExisting histories of social mobility have focused on adults and on measuring the achievement of individual upward mobility. However, children and families were central to mobility strategies. Using the papers of the Heywoods of Bolton, this article examines how the families of the industrial middle class endowed their offspring with the goods and character needed to secure their social standing, highlighting the emotional intricacy of these processes. It demonstrates that such families conceived of social mobility as a familial project and that rather than pursuing upward mobility, their chief objective was to guard against social decline. 相似文献