Physical fitness percentiles for Portuguese children and adolescents aged 10–18 years

Abstract

This study aimed to produce age- and sex-specific physical fitness reference data for Portuguese youth; to report the prevalence of youth in the healthy zone of physical fitness according to the FITNESSGRAM^® criteria; to verify the agreement between the Portuguese physical fitness percentiles and the FITNESSGRAM^® healthy zones. In 2008, 22,048 Portuguese children and adolescents (10–18 years) were evaluated. Physical fitness (curl-ups, push-ups, 20-m shuttle run and modified-back-saver-sit-and-reach tests) was evaluated using the FITNESSGRAM^® Test Battery 8.0. Smoothed percentile curves were estimated using Cole’s LMS method. Boys consistently outperformed girls in every physical fitness test, except for the modified-back-saver-sit-and-reach tests. In both sexes and for all physical fitness tests, higher percentile values were observed at older ages. The 50th percentile of all physical fitness tests had the highest accuracy to discriminate between under healthy zone and healthy zone of the FITNESSGRAM^®. Portuguese schools and physical education teachers may considerer the 50th percentile for age and sex or the FITNESSGRAM^® criteria for classifying participants in the healthy zone as acceptable cut-offs, above which youth should be considered fit. These reference values can be used as normative data and for baseline values for subsequent surveillance of the physical fitness of Portuguese youth.     

Vitamin C supplementation does not influence plasma and blood mononuclear cell IL-6 and IL-10 levels after exercise

Abstract

The aim of this study was to determine whether the highest vitamin C supplementation associated with complete bioavailability influences the plasma and blood mononuclear cell IL-6 and IL-10 response to exercise. A double-blinded study of supplementation with vitamin C was performed. After 15 days of supplementation with vitamin C (500 mg · day^?1, n = 16) or a placebo (n = 15), participants in the study completed a 15-km run competition. Blood samples were taken before and after competition. Oxidative stress markers, antioxidants, cortisol, IL-6 and IL-10 were determined in plasma or serum. IL-6 and IL-10 protein and mRNA levels were measured in blood mononuclear cells. Although higher plasma and blood mononuclear cell vitamin C levels were observed in the supplemented group when compared with the placebo one, the two groups showed identical exercise-induced changes in all the measured parameters. Exercise induced increased IL-6 and IL-10 levels in plasma and blood mononuclear cells. IL-6 and IL-10 mRNA levels in blood mononuclear cells increased after the competition. After recovery, IL-6 mRNA returned to basal levels and IL-10 mRNA levels remained elevated. In conclusion, exercise induced increased IL-6 and IL-10 production in blood mononuclear cells. However, vitamin C supplementation did not influence IL-6 and IL-10 response to exercise.     

Perceived environmental characteristics and psychosocial factors associated with physical activity levels in adolescents from Northeast Brazil: structural equation modelling analysis

Abstract

This study aimed to investigate the direct and indirect associations between perceived environmental characteristics and psychosocial factors and physical activity levels in adolescents from Northeast Brazil. The sample was composed of 2,361 adolescents aged 14–19 years (56.6% female). Physical activity was measured using a questionnaire and environmental (perceived environmental characteristics) and psychosocial (self-efficacy, social support from parents and friends for physical activity) factors with previously validated scales. Perceived environmental characteristics were not directly associated with the levels of physical activity, but exhibited significant indirect associations, mediated by self-efficacy in males. Self-efficacy and social support were positively and directly associated with physical activity levels, and part of the associations between social support and physical activity was mediated by self-efficacy. Perception of self-efficacy and social support, important factors associated with physical activity levels in adolescents, should be the target of interventions aimed at increasing physical activity. Favorable environments for physical activity also need to be considered, since they have a positive influence on the self-efficacy of adolescents.     

Effective Online Instructional and Assessment Strategies

The purpose of this study was to better understand the instructional and assessment strategies that are most effective in the online learning environment. Faculty and students identified several strategies for maintaining instructional quality in the online environment, including the importance of using a variety of instructional methods to appeal to various learning styles and building an interactive and cohesive learning environment that includes group work. Online assessment strategies include having a wide variety of clearly explained assignments on a regular basis and providing meaningful and timely feedback to students regarding the quality of their work. Effective assessment techniques include projects, portfolios, self-assessments, peer evaluations, and weekly assignments with immediate feedback. The role of meaningful feedback cannot be overemphasized.     

Comparing Faculty and Student Perceptions Regarding Factors That Affect Student Retention in Online Education

This qualitative study compared faculty and student perceptions regarding factors that affect student retention in online courses in an attempt to more effectively address the problem of attrition. A grounded study method was used to interview students taking online courses, analyze their responses related to the critical factors that affect student retention, and compare them with those given by expert online faculty documented by Gaytan (2013). Among the various findings, two are considered critical: online students would like to receive more instruction from their professors and more comprehensive feedback that would allow them to engage in corrective behaviors to improve performance. Comparing faculty and student responses related to the factors that affect student retention could give online program administrators and faculty advisors a better understanding of these critical factors to be able to respond to the student retention challenge more effectively.     

Local Equating Using the Rasch Model,the OPLM,and the 2PL IRT Model—or—What Is It Anyway if the Model Captures Everything There Is to Know About the Test Takers?

Local equating (LE) is based on Lord's criterion of equity. It defines a family of true transformations that aim at the ideal of equitable equating. van der Linden (this issue) offers a detailed discussion of common issues in observed‐score equating relative to this local approach. By assuming an underlying item response theory model, one of the main features of LE is that it adjusts the equated raw scores using conditional distributions of raw scores given an estimate of the ability of interest. In this article, we argue that this feature disappears when using a Rasch model for the estimation of the true transformation, while the one‐parameter logistic model and the two‐parameter logistic model do provide a local adjustment of the equated score.     

Fellows' Perceptions of a Mandatory Reflective Electronic Portfolio in a Geriatric Medicine Fellowship Program

Electronic portfolios (ePortfolios) can be useful for evaluating and documenting mastery of competencies. We investigated geriatric medicine fellows' perceptions of an ePortfolio. We conducted surveys and focus groups followed by quantitative and qualitative data analysis. Our study revealed that fellows considered the ePortfolio acceptable and accessible. Fellows reflected on aspects relevant to postgraduate training and future practice and documented adherence to competencies. However, fellows expressed resentment about the self-reflection component, which interfered with the overall acceptance of the ePortfolio. Although ePortfolios can be powerful and reflective tools for competency assessment, care must be taken in their implementation.     

Against the odds: resilience in mathematics students in transition

This paper examines ‘resilience’ of mathematics students in transition from a sociocultural perspective, in which resilience is viewed as relational and in particular as a function of the social and cultural capital students may bring to the new field. We draw on two students’ stories of transition, in which we recognise elements traditionally viewed as ‘risks’ for mathematics students in transition into institutions where new demands are made. However, in each case it seems that some of their apparent background ‘risk factors’—coming from poorer socioeconomic backgrounds and disadvantaged schools—have come to serve to constitute capital, buttressing their particular resilience, as they provide a crucial kind of autonomy that is particularly valued in the new institution. We identify the learners’ reflexivity as having been crucial to this accumulation of capital and we discuss some educational implications.