Effects of plyometric jump training in female soccer player’s vertical jump height: A systematic review with meta-analysis

ABSTRACT

To assess the effects of plyometric jump training (PJT) in female soccer player’s vertical jump height, a review was conducted using the data sources PubMed, MEDLINE, Web Of Science and SCOPUS. Only peer-review articles were included. To qualify for inclusion in the meta-analysis, studies must have included (i) a PJT programme of at least 2 weeks, (ii) cohorts of healthy female soccer players with no restriction for age, (iii) a control group, (iv) a measure of countermovement jump (CMJ). The inverse variance random-effects model for meta-analyses was used. From 7,136 records initially identified through database searching, 8 were eligible for meta-analysis, comprising 9 training groups (n = 99) and 9 control groups (n = 94). The magnitude of the main effect was moderate (ES = 1.01 [95%CI = 0.36–1.66], Z = 3.04, p = 0.002). Sub-group analyses were performed (i.e., PJT frequency, duration and total number of sessions), revealing no significant subgroup differences (p = 0.34–0.96). Among the studies included in this review, none reported injury or other adverse effects. In conclusion, PJT is effective in female soccer players for the improvement of vertical jump height. In future, research must identify specific dose–response relationships following PJT, particularly in the long term.     

Segment coupling and coordination variability analyses of the roundhouse kick in taekwondo relative to the initial stance position

The initial stance position (ISP) has been observed as a factor affecting the execution technique during taekwondo kicks. In the present study, authors aimed to analyse a roundhouse kick to the chest by measuring movement coordination and the variability of coordination and comparing this across the different ISP (0°, 45° and 90°). Eight experienced taekwondo athletes performed consecutive kicking trials in random order from every of the three relative positions. The execution was divided into three phases (stance, first swing and second swing phase). A motion capture system was used to measure athletes’ angular displacement of pelvis and thigh. A modified vector coding technique was used to quantify the coordination of the segments which contributed to the overall movement. The variability of this coordination (CV) for each ISP was also calculated. Comparative analysis showed that during the stance phase in the transverse plane, athletes coordinated movement of the trunk and thigh with a higher frequency of in-phase and lower frequency of exclusive thigh rotation in the 0° stance than the 90° stance position (P < 0.05). CV was also influenced by the different ISP. During the first swing and the majority of the second swing phase, predominant in-phase coordination of the pelvis and thigh was observed. Including exercises that require in-phase movement could not only help athletes to acquire coordination stability but also efficiency. The existence of a constraint such as ISP implies an increase of the variability when the athletes have to kick from ISP they are not used to adopt (i.e., 0° and 90° ISP) as an evidence of adaptability in the athletes’ execution technique.     

Teachers in retreat: The teacher as a dialogical self and the risks of an excessive formalization of its role

The aim of this paper is to explore the identity of the teacher as a dialectical being that is in permanent construction, to identify some obstacles teachers might find in this process while operating in an institutional framework, and the effects these could have upon the teacher and the goals she pursues with her students. By ruling out the idea of identity as an autonomous self that can be constructed with no ties with its context, we propose that identity is dialogical and is built through the relationships we establish with others. This fact situates the relationship between the student and the teacher at the center of pedagogical practices and allows us to establish the ideas of teacher presence and integrity as central elements for the moral development of students. In this context, we identify the excessive institutionalization of the role of the teacher as a cause for the reduction of identity and a defensive retreat to the possible outcomes of being judged by strictly formal criteria, which in turn can hinder the relation between student and teacher and risks possible negative consequences in the moral growth of both.     

A public value perspective for ICT enabled public sector reforms: A theoretical reflection

The purpose of this paper is to offer a critical discussion of information system adoption in the public sector (often referred to as e-government) and to contribute to the debate by offering a public value perspective. The paper points to the public value paradigm as an alternative approach to studying ICT-enabled public sector reforms. This paradigm, we argue, proposes an alternative way of framing the nature of the problems faced when ICT enabled public sector reforms are initiated and studied. The public value perspective proposes a new and richer context in which to study and research these phenomena. It also calls for the redefinition of the ways we assess e-government in the context of public sector reforms. It is therefore seen as vital to evaluate the socio-political impact of ICT adoption in the public sector.     

Measuring the effectiveness of online problem solving for improving academic performance in a probability course

Education and Information Technologies - Research on impact in student achievement of online homework systems compared to traditional methods is ambivalent. Methodological issues in the study...     

How does mental fatigue affect soccer performance during small-sided games? A cognitive,tactical and physical approach

ABSTRACT

Objectives

We examine how mental fatigue (MF) influences peripheral perception, tactical behaviour, and physical performance of soccer players during a standardized small-sided game.     

The Project ‘Art for Learning Art’ in Contemporary Art Museums

Projection‐based augmented reality and virtual reality are used in a visual arts‐based educational project in contemporary art museums from an a/r/tographic perspective. The project ‘Art for Learning Art’ (in Spanish, Arte para aprender arte), at the Museo CajaGRANADA in Granada (Spain) has been developed in collaboration with the University of Granada since 2013. We have employed creative, educational and research methodologies inspired by exhibited works in art museums to encourage visual feedback of visitors participating in collaborative installations. Two such experiences also were produced at the Tate Liverpool Gallery and Museum in March 2018; utilising the methodology of mediation through projection‐based augmented reality and virtual reality, which introduces facets of visual and physical experience that alter the whole experience for the museum's public. By putting on virtual reality headsets, and playing with physical movements, we generate images and change the projections in the museum using projection‐based augmented reality to disrupt the way the public typically moves in the museum. The purpose of the developed interrelations with artworks in the Museo CajaGRANADA and the Tate Liverpool Gallery and Museum was to create collaborative digital images by playing with select artworks exhibited in the museums’ collections. We use this kind of mediation in art museums to develop a visual understanding to provoke learning about art through art creation in a contemporary way. The results are extraordinary as images; they are collaborative artworks, which connect visually with the artworks in the exhibition.