The relative age effect on physical fitness in preschool children

ABSTRACT

The aim of the present study was to investigate the existence of a relative age effect (RAE) on physical fitness of preschoolers. Anthropometry and physical fitness were assessed in 3147 children (3–5 years old) using the PREFIT battery. Based on the birth year, participants were divided into 3year groups (3-, 4- and 5-years). Within each year group, 4quarter groups were created: quarter 1, preschoolers born from January to March; quarter 2, from April to June; quarter 3, from July to September; quarter 4, from October to December. The MANCOVA analysis revealed a main effect of year group (Wilks’ λ = 0.383; F_10,5996 = 369.64; p < 0.001, η_p ² = 0.381) and of quarter (Wilks’ λ = 0.874; F_15,8276.6 = 27.67; p < 0.001; η_p ² = 0.044) over the whole battery of tests. To the best of our knowledge, this is the first study to report the existence of RAE at the preschool stage. In general, performance improved as the relative age increased (i.e., those born in quarter 1 performed better than those in the other quarters). Individualization strategies should be addressed within the same academic year not only in elementary or secondary years but also in preschoolers.     

Innovative moments and narrative change in career counselling: a case study

International Journal for Educational and Vocational Guidance - This case study of an undecided university student has two aims: to assess the effect of life design career counselling on...     

Educational knowledge generation from administrative data

Most universities use Information Systems (IS) to perform their daily administrative activities (student enrollment, data files, accountancy, etc.), and an integrated Learning Management System (LMS) to support teaching and learning. However, although a lot of effort has been put into deploying these computerized systems, the data that they provide are not fully exploited from an educational perspective. In this paper we describe a case in which these data have been used to identify relevant relations between the general use of the LMS, the existence of teaching innovation programs and the quality of education. The method used can be easily generalized and employed in other different contexts, to derive meaningful information on the impact that some variables may have over others.     

The building of weak expertise: the work of global university rankers

University rankers are the subject of much criticism, and yet they remain influential in the field of higher education. Drawing from a two-year field study of university ranking organizations, interviews with key correspondents in the sector, and an analysis of related documents, I introduce the concept of weak expertise. This kind of expertise is the result of a constantly negotiated balance between the relevance, reliability, and robustness of rankers’ data and their relationships with their key readers and audiences. Building this expertise entails collecting robust data, presenting it in ways that are relevant to audiences, and engaging with critics. I show how one ranking organization, the Times Higher Education (THE), sought to maintain its legitimacy in the face of opposition from important stakeholders and how it sought to introduce a new “Innovation and Impact” ranking. The paper analyzes the strategies, methods, and particular practices that university rankers undertake to legitimate their knowledge—and is the first work to do so using insights gathered alongside the operations of one of the ranking agencies as well as from the rankings’ conference circuit. Rather than assuming that all of these trust-building mechanisms have solidified the hold of the THE over its audience, they can be seen as signs of a constant struggle for influence over a skeptical audience.     

Huelga Schools in Houston: Community-Based Education in the Struggle for Legal Recognition, 1970

This essay provides an overview of the huelga schools established in Houston, Texas, in 1970. For 2 years, from 1970 to 1972, the Mexican American community opposed the Houston Independent School District’s plan to integrate the schools by pairing so-called White Mexican Americans with African American students. While they protested this decision, Mexican Americans also established huelga or strike schools in order to provide their children with basic skills in education and to explain the meaning and significance of their political actions. This is the history of the huelga schools established in the 1st months of this struggle.     

Delinking rhetorics of neoliberalism: An analysis of South American leftist presidents’ speeches

We analyze the so-called Socialism of the twenty-first century in which nine South American governments turned to the left over the last 15 years. This South American socialist turn is seen as a delinking from the logics of dependency and pure neoliberalism. To explore the rhetorics that underlie this delinking process, we conducted both a macroanalysis and an intradiscursive rhetorical analysis of the inauguration and most significant speeches of all of the leftist South American presidents elected after 1999. We claim that a common critique of neoliberalism underlies the South American presidents’ speeches, which manifests through specific rhetorics concerning participatory democracy, social inclusion, and environmental protection. When they became transnational, these delinking rhetorics crafted a decolonial critique that calls for more indigenous models of development.     

Aerobic fitness and physical activity are inversely associated with body fat,dyslipidemia and inflammatory mediators in children and adolescents living with HIV

This study aimed to investigate if moderate to vigorous physical activity (MVPA) and aerobic fitness are associated with cardiovascular risk factors in HIV+ children and adolescents. Sixty-five children and adolescents (8 to 15 years) provided minutes of MVPA measured by accelerometers and peak oxygen uptake (peak VO₂) by breath-by-breath respiratory exchange. Cardiovascular risk factors were characterized by body fat, blood pressure, total cholesterol, HDL-c, LDL-c, triglycerides, glucose, insulin, C-reactive protein (CRP), interleukin (IL)-6, tumor necrosis factor-alpha (TNF-α) and carotid intima-media thickness. Results indicated that higher MVPA was associated with lower values of total (β = ?3.566) and trunk body fat (β = ?3.495), total cholesterol (β = ?0.112) and LDL-c (β = ?0.830). Likewise, higher peak VO₂ was associated with lower total (β = ?0.629) and trunk body fat values (β = ?0.592) and levels of CRP (β = ?0.059). The physically active participants had lower total cholesterol (?24.4 mg.dL^?1) and LDL-c (?20.1 mg.dL^?1) compared to participants judged to be insufficiently active. Moreover, participants with satisfactory peak VO? showed lower total (?4.1%) and trunk (?4.3%) body fat, CRP (?2.3 mg.L^?1), IL-6 (?2.4 pg.mL^?1) and TNF-α (?1.0 pg.mL^?1) compared to low peak VO₂ peers. High levels of MVPA and aerobic fitness may prevent developing of cardiovascular risk factors in children and adolescents HIV+.     

Multimedia search capabilities of Chinese language search engines

This paper reports results from a study exploring the multimedia search functionality of Chinese language search engines. Web searching in Chinese (Mandarin) is a growing research area and a technical challenge for popular commercial Web search engines. Few studies have been conducted on Chinese language search engines. We investigate two research questions: which Chinese language search engines provide multimedia searching, and what multimedia search functionalities are available in Chinese language Web search engines. Specifically, we examine each Web search engine’s (1) features permitting Chinese language multimedia searches, (2) extent of search personalization and user control of multimedia search variables, and (3) the relationships between Web search engines and their features in the Chinese context. Key findings show that Chinese language Web search engines offer limited multimedia search functionality, and general search engines provide a wider range of features than specialized multimedia search engines. Study results have implications for Chinese Web users, Website designers and Web search engine developers.     

Sexual dimorphism in bone–muscle relationship in young adults

The purpose of this study was to analyse associations between lean soft tissue (LST), a surrogate of skeletal muscle mass and key fracture-related geometric characteristics of the proximal femur. Moreover, we examined the role that muscle played on the proximal femur geometry in response to physical activity (PA). Participants were 83 young adults. Leg LST (exposure) was assessed by dual energy X-ray absorptiometry (DXA). Proximal femur geometry was derived from a left hip DXA scan. Geometric variables (outcomes) included the femoral neck axis length (FNAL), the femoral neck width (FNW), the neck–shaft angle and FNW|FNAL (an index of robustness). PA was evaluated by accelerometry. Linear regression was used to analyse relationships. Additional exposure variables included body height and mass. In males, leg LST explained 17.4% of variation in FNAL (P < 0.001) and 15% in FNW (P = 0.015). In females, it explained 8.8% of the variance in FNAL (P = 0.020). Associations remained significant in males, but not in females, when vigorous PA was added to the models. These results suggest that public health approaches to promote PA may be particularly important in females since vigorous PA seems to convey advantages in femur geometry and consequently in bone strength.