Spatial-temporal constraints on decision-making during shooting performance in the team sport of futsal

Abstract

In this paper we examined the influence of opposing players constraining the decision-making of an attacker during shooting performance in futsal. Performance during 10 competitive matches was recorded and examined from the moment a shot was taken until the ball was intercepted or entered the goal in sequences of play: ending in a goal, a goalkeeper's save, or an interception by the nearest defender. The variables under scrutiny in this study were (i) the distance of each player to the ball's trajectory, (ii) the time for the ball to arrive at that same point (i.e. the interception point), and (iii), the required movement velocity of the nearest defender and the goalkeeper to intercept the ball. Results showed that values of distance from a defender and goalkeeper to the interception points were significantly lower when they intercepted the ball. The time of ball arrival at the interception point of the defender was also lower when the ball was intercepted. The required velocities of the nearest outfield defender and the goalkeeper to intercept the ball were significantly lower during plays in which they intercepted the ball, than in plays in which the ball was not intercepted. Our results suggest that researchers and practitioners should consider simultaneously both space and time in analysis of interceptive actions in team sports. The required movement velocities of the opponents to intercept the ball are reliable spatial-temporal variables constraining decision-making during shooting performance in team sports like futsal.     

Characteristics of extracurricular physical activity and cognitive performance in adolescents. The AVENA study

Abstract

The aim of this report was to examine the associations between some characteristics (i.e., structure and number) of extracurricular physical activity (EPA) and cognitive performance in adolescents. A total of 1662 adolescents (880 girls; 13.0–18.5 years) from 5 Spanish cities (Granada, Madrid, Murcia, Santander and Zaragoza) were included in this study. Structure (organised and non-organised) and number of EPAs, and participation at vigorous intensity during EPA were self-reported. Cognitive performance (verbal, numeric and reasoning abilities, and an overall score) was measured with the “SRA-Test of Educational Ability”. Results showed that vigorous EPA was positively associated with all cognitive variables. Adolescents who practiced an organised EPA had higher scores in 3 of the 4 cognitive variables than those who practiced a non-organised EPA (all P < 0.05). Likewise, the group who participated in more than one EPA had higher cognitive performance in all variables than the group who participated in only one EPA (all P < 0.05). Regardless of potential confounder variables, including vigorous EPA, both structure and number of EPAs were each other independently associated with cognitive performance. Therefore, structure and number of EPAs may positively influence cognitive performance in adolescents. Participating in multiple, organised EPA may have benefits for cognitive performance.     

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.     

Intermittent hypoxia exposure in a hypobaric chamber and erythropoietin abuse interpretation

Abstract

The aim of this study was to assess the effect of intermittent hypoxia exposure on direct and indirect methods used to evaluate recombinant human erythropoietin (rhEPO) misuse. Sixteen male triathletes were randomly assigned to either the intermittent hypoxia exposure group (experimental group) or the control normoxic group (control group). The members of the experimental group were exposed to simulated altitude (from 4000 to 5500 m) in a hypobaric chamber for 3 h per day, 5 days a week, for 4 weeks. Blood and urine samples were collected before and after the first and the final exposures, and again 2 weeks after the final exposure. While serum EPO significantly increased after the first [from a mean 8.3 IU · l^?1 (s = 3.2) to 16.6 IU · l^?1 (s = 4.7)] and final exposures [from 4.6 IU · l^?1 (s = 1.4) to 24.8 IU · l^?1 (s = 9.3)], haemoglobin, percentage of reticulocytes, and soluble transferrin receptor were not elevated. Second-generation ON/OFF models (indirect rhEPO misuse detection) were insensitive to intermittent hypoxia exposure. The distribution of the urinary EPO isoelectric profiles (direct rhEPO misuse detection) was altered after intermittent hypoxia exposure with a slight shift towards more basic isoforms. However, those shifts never resulted in misinterpretation of results. The intermittent hypoxia exposure protocol studied did not produce any false-positive result for indirect or direct detection of rhEPO misuse in spite of the changes in EPO serum concentrations and urinary EPO isoelectric profiles, respectively.     

Progression in Complexity: Contextualizing Sustainable Marine Resources Management in a 10th Grade Classroom

Sustainable management of marine resources raises great challenges. Working with this socio-scientific issue in the classroom requires students to apply complex models about energy flow and trophic pyramids in order to understand that food chains represent transfer of energy, to construct meanings for sustainable resources management through discourse, and to connect them to actions and decisions in a real-life context. In this paper we examine the process of elaboration of plans for resources management in a marine ecosystem by 10th grade students (15–16 year) in the context of solving an authentic task. A complete class (N = 14) worked in a sequence about ecosystems. Working in small groups, the students made models of energy flow and trophic pyramids, and used them to solve the problem of feeding a small community for a long time. Data collection included videotaping and audiotaping of all of the sessions, and collecting the students’ written productions. The research objective is to examine the process of designing a plan for sustainable resources management in terms of the discursive moves of the students across stages in contextualizing practices, or different degrees of complexity (Jiménez-Aleixandre & Reigosa International Journal of Science Education, 14(1): 51–61 2006), understood as transformations from theoretical statements to decisions about the plan. The analysis of students’ discursive moves shows how the groups progressed through stages of connecting different models, between them and with the context, in order to solve the task. The challenges related to taking this sustainability issue to the classroom are discussed.     

Developing Generic Competences in the European Higher Education Area: a proposal for teaching the principles of economics

The participation of Spain in the European Higher Education Area (EHEA) involves a number of important challenges for academics. Adapting to an educational model that is characterised by competence-based teaching is a difficult task, yet it is of paramount importance in the context of current reforms. In an educational system in which the traditional lecture prevails, learning-centred teaching represents a major cultural change with significant consequences. The objective of this study is to offer economics lecturers some practical techniques for use in the classroom. Specifically, it includes suggestions for the planning, preparation and teaching of lectures, seminars, tutorials, case studies, debates, and computer-based learning. It also provides practical advice on student assessment.     

What do graduates think? An analysis of intention to repeat the same studies and university

The present work analyzes the key factors in the university experience that influence graduates' intention to repeat the same studies and the same institution, given the hypothetical option – based on hindsight – of selecting afresh a course and place of study. The work is inspired by the theory of planned behavior [Ajzen, I. (1985). From intentions to actions: A theory of planned behavior, in action control: From cognition to behavior. New York: J. Kuhl and J. Beckmann; Ajzen, I. (1991). The theory of planned behavior. Organizational Behavior and Human Decision Processes, 50, 179–211]. This analysis is based on the opinion of graduates in relation to a set of variables that together form the intention to repeat, namely quality of education; services and facilities; preparation by the university for employment; fitness-for-purpose of studies for the job market; capacities and skills acquired; the time taken to find work following graduation; current salary; and satisfaction with current employment. Using multiple regression models, the principal components of service quality in a university context are determined. The findings indicate that the quality of the educational process is the most influential aspect both in the intention to repeat the same studies and also in the intention to repeat the same university. Services and facilities have a marked influence on the latter, while the time taken to find employment and current salary are the two aspects with the least impact.     

On the acquisition of some basic word spelling mechanisms in a deep (French) and a shallow (Spanish) system

An experiment was carried out to compare the time course of the acquisition of two basic spelling mechanisms in Spanish, a shallow system, and French, a deep system. The first was lexical. It relies on the orthographic lexicon, a hypothetical structure containing the orthographic representations of words accessible for word spelling. To evaluate its contribution the participants were asked to spell words of high and low frequency containing phonemes which can take different graphemic values. The second mechanism relies on sub-lexical processes. Its contribution was evaluated asking the participants to spell words containing consistent phoneme-to-grapheme translation pairs which were identical in Spanish and French. Two contrasting predictions were considered, one derived from the Orthographic Depth Hypothesis (ODH, Frost, 2005) and the other from the Self-Teaching Hypothesis (STH, Share, 2004). According to the ODH, the orthographic lexicon should develop more rapidly in French than in Spanish because Spanish spellers can rely on phoneme-to-grapheme translation mechanisms to spell most words, meaning that they do not need to resort to the orthographic lexicon. In contrast, the STH suggests that effective identification of a word gradually generates its orthographic representation. The results revealed that both spelling mechanisms develop far faster in Spanish than in French. The fact that word frequency effects appeared earlier in Spanish than in French, indicating that the orthographic lexicon incorporates words more rapidly in a shallow than in a deep system, is clearly incompatible with the ODH and easier to handle in the context of the STH.