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121.
The aim of this study was to determine which physiological variables predict excellence in middle- and long-distance runners. Forty middle-distance runners (age 23 ± 4 years, body mass 67.2 ± 5.9 kg, stature 1.80 ± 0.05 m, VO(2max) 65.9 ± 4.5 ml · kg(-1) · min(-1)) and 32 long-distance runners (age 25 ± 4 years, body mass 59.8 ± 5.1 kg, stature 1.73 ± 0.06 m, VO(2max) 71.6 ± 5.0 ml · kg(-1) · min(-1)) competing at international standard performed an incremental running test to exhaustion. Expired gas analysis was performed breath-by-breath and maximum oxygen uptake (VO(2max)) and two ventilatory thresholds (VT(1) and VT(2)) were calculated. Long-distance runners presented a higher VO(2max) than middle-distance runners when expressed relative to body mass (P < 0.001, d = 1.18, 95% CI [0.68, 1.68]). At the intensities corresponding to VT(1) and VT(2), long-distance runners showed higher values for VO(2) expressed relative to body mass or %VO(2max), speed and oxygen cost of running (P < 0.05). When oxygen uptake was adjusted for body mass, differences between groups were consistent. Logistic binary regression analysis showed that VO(2max) (expressed as l · min(-1) and ml · kg(-1) · min(-1)), VO(2VT2) (expressed as ml · kg(-0.94) · min(-1)), and speed at VT(2) (v(VT2)) categorized long-distance runners. In addition, the multivariate model correctly classified 84.7% of the athletes. Thus, VO(2max), VO(2VT2), and v(VT2) discriminate between elite middle-distance and long-distance runners.  相似文献   
122.
The purpose of the present study was to investigate the socio-demographic and lifestyle determinants of physical activity practice, as well as the motivations for being or not being physically active in Spanish university students. A representative sample of students from a Spanish university (n = 2,051; 42.1% males; mean age 21.9, s = 4.8 years) participated in the present cross-sectional study. A questionnaire including questions regarding lifestyle, dietary habits, parents' characteristics, and physical activity habits was administered to the students. The socio-demographic and lifestyle determinants of physical activity practice were assessed using multivariable logistic regression. 68.4% of men and 48.4% of women reported to practise physical activity in the present sample. Those who practised physical activity consumed more fruits and were less likely to be smokers compared to non-physically active students. Also, physically inactive men spent more time in front of the computer and physically inactive women spent more time in front of the TV and were more likely to be frequent alcohol consumers. Maternal educational level and maternal physical activity habits were also important determinants of physical activity practice among men and women respectively. In conclusion, physically active students tended to engage in other healthy habits in the present population, suggesting the clustering of healthy or unhealthy lifestyle factors among specific subgroups.  相似文献   
123.
This study seeks to discover whether handball goalkeepers employ a general anticipatory strategy when facing long distance throws and the effect of uncertainty on these strategies. Seven goalkeepers and four throwers took part. We used a force platform to analyse the goalkeeper's movements on the basis of reaction forces and two video cameras synchronised at 500 Hz to film the throw using 3D video techniques. The goalkeepers initiated their movement towards the side of the throw 193 ± 67 ms before the release of the ball and when the uncertainty was reduced the time increased to 349 ± 71 ms. The kinematics analysis of their centre of mass indicated that there was an anticipatory strategy of movement with certain modifications when there was greater uncertainty. All the average scores referring to velocity and lateral movement of the goalkeeper's centre of mass are significantly greater than those recorded for the experimental situation with bigger uncertainty. The methodology used has enabled us to tackle the study of anticipation from an analysis of the movement used by goalkeepers to save the ball.  相似文献   
124.
In this study, we used tensiomyography (TMG) to assess muscle status immediately after an ultra-endurance triathlon. Maximal radial displacement or deformation of the muscle belly, contraction time, delay time, sustain time, and relaxation time were measured for both legs, and dependent t-tests were used to compare means between the beginning and end of the race. The 19 men assessed (age 37.9 ± 7.1 years; height 177.5 ± 4.6 cm; weight: 73.6 ± 6.5 kg) participated in the 2009 edition of the Lanzarote Ironman. Deterioration in the neural response was observed for contraction time (P = 0.008) and relaxation time (P = 0.011), with a moderate decrease in the response time (sustain time) and a loss in muscle stiffness (deformation of the muscle belly). The effect of muscle fatigue on the rectus femoris and biceps femoris was different. Barely any changes in contraction time, relaxation time, sustain time, and deformation of the muscle belly were observed, while only the contraction response time decreased to a significant extent (reduction in delay time; P = 0.003). The considerable loss in contractile capacity induced by a long-distance race was reflected in changes in the neuromuscular response and fluctuations in the contractile capacity of the muscle. These modifications, derived from a prolonged, exhausting effort, can be assessed in a simple, non-aggressive, non-invasive way using tensiomyography.  相似文献   
125.
This article examines the determinants of the salaries that Spanish university graduates earn on the labor market. Different earnings equations are estimated that allow us to measure the economic returns to investment in human capital at the university level, demonstrating that: on the one hand, considering schooling to be an exogenous variable gives a downward bias to the estimations of the private rates of return to an university education; on the other hand, not taking into account the aspects of the demand-side of the labor market in the traditional Mincerian earnings function, even though schooling is considered as an endogenous variable, the rates of return estimated for an university education would be given an upward bias. The problem concerning the endogeneity of schooling has been corrected in this article by using the instrumental variables technique.  相似文献   
126.
The main objective of this paper is to analyse the effect of the affordances of a virtual learning environment and a personal learning environment (PLE) in the configuration of the students' personal networks in a higher education context. The results are discussed in light of the adaptation of the students to the learning network made up by two undergraduate, inter-university and online courses. Besides, we also examine the influence of this effect in the learning process. The findings reflect the effectiveness of a PLE for facilitating student participation and for assisting students in the creation of larger and more balanced personal networks with richer social capital. However, the findings do not provide evidences about a difference in the learning performance between the two environments. From a methodological point of view, this paper serves as an illustration of the analysis of personal networks on digital data collected from technology-enhanced learning environments.  相似文献   
127.
128.
ABSTRACT

Inclusive education of disabled students has been promoted in European disability policies. However, the transition process from more segregated system is slow. The purpose of this study was to provide an insight about different types of schooling of disabled children affected by a rare disease across Europe and to evaluate their and caregivers’ well-being. We analysed data from a cross-sectional study (BURQOL-RD) of persons with rare diseases that cause intellectual and/or physical disability: Prader-Willi syndrome, fragile X syndrome, three types of mucopolysaccharidosis and Duchenne muscular dystrophy. The sample consisted of 359 children aged 6–17 and 269 caregivers from eight European countries. Results showed differences between countries in proportion of students placed in special schools, which are still valid option in countries such as Germany, France or UK. Within the inclusive education modalities, lack of special support for disabled students was observed especially in low-income countries. No association between the type of schooling and quality of life was observed, but the subjective caregivers’ burden seems to be higher in special schools. The study shows existent differences in implementation of inclusive education in Europe. More research is needed in the field of rare disease disability and educational needs.  相似文献   
129.
Abstract

High-achieving African American students in California are not attending University of California (UC) campuses. Due to hyper-implementations of Proposition 209, which limited UC campuses’ ability to use race as a significant admission criteria, the UC system and individual UC campus policies have scaled back their efforts to recruit high-achieving African American students from California. This article presents findings from the qualitative portion (n?=?74) of a convergent mixed-method study of over 700 African American college-going students. Findings convey the critical role that access, outreach, diversity, and climate plays in the college choice process of African American high achievers. Drawing upon higher education and critical race literature, the findings further reveal the challenges and opportunities for states and elite universities in retaining its brightest students from diverse backgrounds. This research also conveys the potential of research to inform state, systemic, and institutional policies to increase access to selective public universities.  相似文献   
130.
This paper presents a review and assessment of existing theoretical accounts to explain differentials in access to education and training in advanced economies. These theories tend to focus on the analysis of the influence of a set of economic, sociological and political variables on access to education. Existing theories are criticized on two grounds. Firstly, they seldom take into consideration the crucial role of political‐institutional factors, and in particular, welfare states’ actions through direct investment and regulation in shaping access levels. Secondly, they focus narrowly on the analysis of different stages of education and training, and this does not reflect the current policy emphasis on lifelong learning. The paper concludes with an outline of a future research agenda to address these gaps, and also calls for a more rigorous analysis of the weight of the different factors affecting access.  相似文献   
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