Variable training: effects on velocity and accuracy in the tennis serve

Abstract

Variable practice has been shown to be an effective strategy to improve open motor skills. However, the usefulness of this procedure in closed motor skills remains controversial. The following study has the objective of analysing the effects of variability practice in the improvement of a closed skill. The skill studied has been the tennis serve. Thirty young tennis players (13 ± 1.52 years), divided in two groups, took part in this study. One group practiced in variable conditions and the other group in consistency conditions. Both groups performed 12 training sessions (60 serves/session). The variable practice group improved their accuracy significantly compared with the consistency group (F_3.25 = 3.078; P = 0.035). The velocity of serve increased after training in both groups (F_3.25 = 15.890; P = 0.001). The practice in variable conditions seems to be effective in improving the performance of the tennis serve.     

List of Reviewers

The aim of this study was to investigate the effects of target distance on temporal and impact force parameters that are important performance factors in taekwondo kicks. Forty-nine taekwondo athletes (age = 24.5 ± 5.9 years; mass = 79.9 ± 10.8 kg) were recruited: 13 male experts, 21 male novices, 8 female experts, and 6 female novices. Impact force, reaction time, and execution time were computed. Three-way repeated measure ANOVAs revealed significant ‘distance’ effect on impact force, reaction time, and execution time (p = 0.001). Comparisons between distance conditions revealed that taekwondo athletes kicked with higher impact force from short distance (17.6 ± 7.5 N/kg) than from long distance (13.1 ± 5.7 N/kg) (p < 0.001), had lower reaction time from short distance (498 ± 90 ms) and normal distance (521 ± 111 ms) than from long distance (602 ± 121 ms) (p < 0.001), and had lower execution time from short distance (261 ± 69 ms/m) than from normal distance (306 ± 105 ms/m) or from long distance (350 ± 106 ms/m) (p = 0.003 and p < 0.001, respectively). In conclusion, target distance affected the kick performance; as distance increases, impact force decreased and reaction time increased. Therefore, when reaction to a simple visual stimulus is needed, kicking from a long distance is not recommended, as longer time is required to respond.     

High school ranks and admission tests as predictors of first year medical students' performance

This article focuses on the predictive values of certain academic variables, high school ranks and admission tests, as related to grades at the end of the first year of the Licenciate in Medicine in Spain. Multiple regression equations were calculated for each first year subject. Multiple R values ranged from 0.41 to 0.61 which implies explained variance percentages of 16.5 and 37.5. The best predictor was found to be the high school grade point average in science courses, the global examination and the admission test average. The importance of taking into account these variables in the admission process is considered. Also the inclusion of some aptitudinal variables is discussed. Finally the need to establish prediction performance tables to be used in the counselling process of admitted students is considered.This is based on a paper presented at the 8th Annual Meeting of the Spanish Society for Medical Education held at Zaragoza on 26–27 October 1984.     

Development and validation of ageist myths in a psychotherapy questionnaire (AMPQ): professional ageism among psychology graduate students

ABSTRACT

Ageism is a problem in aging societies. Clinical psychologists and undergraduate psychology students have shown negative attitudes toward older adults. However, no speci?c measure against ageist myths in the psychotherapeutic context is available. This study aims to develop and present the psychometric properties of the Ageist Myths about Psychotherapy Questionnaire (AMPQ).

These issues were examined by surveying 222 psychology graduates at higher education institutions about their attitudes and behaviors concerning psychotherapy with older adults, negative stereotypes toward aging, and attitudes toward dementia.

Using principal components analysis, 10 items were retained and one factor was obtained with an acceptable reliability index. Signi?cant associations were found between the AMPQ and negative stereotypes toward aging, and attitudes toward dementia.

Results revealed that universities and colleges with psychology programs have an ageist bias. Implications for college formation in aging, and older adults with mental health problems, are discussed and presented.     

Training Planning and Working Memory in Third Graders

Working memory and planning are fundamental cognitive skills supporting fluid reasoning. We show that 2 games that train working memory and planning skills in school‐aged children promote transfer to 2 different tasks: an attentional test and a fluid reasoning test. We also show long‐term improvement of planning and memory capacities in 8‐year‐old children after playing adaptive computer games specifically tailored to entrain these cognitive functions. Working memory capacity expanded from 5 to 7 items by using our games. Furthermore, steady progression in the task indicates that this capacity can be trained rapidly. Planning abilities persisted in a nonmarkovian form of play, where a move is highly influenced by previous moves, avoiding back‐ups. Here, we introduce a public and growing platform ( http://www.matemarote.com.ar/ ) developed for this research which has the potential for wide use in educational research.     

Turkish Prospective Chemistry Teachers’ Beliefs about Chemistry Teaching

Given the progressive loss of influence for the school relative to television in youngsters’ everyday lives, this article describes the procedure and the results of including cartoons in the physics curriculum in secondary education. Work was carried out intensively with a small group of pupils and sporadically with a larger group. In the first case, cartoons were used for identifying and discussing fictitious phenomena, problem‐solving, and assessment of the learning. In the second case, for identifying and discussing fictitious phenomena, a quasi‐experimental research design was followed. The results back the use of this didactic tool as an element for motivating and invigorating the classroom, for identifying the pupils’ alternative ideas and the assessment of their learning, as well as for a more critical way of watching television.     

Theory in the flesh: Toward an endarkened epistemology

In her article "The substance of things hoped for, the evidence of things not seen: Examining an endarkened feminist epistemology in educational research and leadership," Professor Dillard delineates a set of proposals for the study of educational inequity. Professor Wright in his response, "An endarkened feminist epistemology? Identity, difference and the politics of representation in educational research," comments on Professor Dillard's proposals and furthers her analysis by an integration of the cultural studies literature. The author enjoins this conversation in this article by reviewing the proposals by feminists of Color to further social justice in solidarity with Professor Dillard's analysis. In particular, feminists of Color are examined, expanding the definition of "data" to include artistic production such as poetry, personal reflections, and autobiographical essays. The integration of spirituality as it relates to secular teaching is another innovation proposed by various writers. Feminists of Color have also chosen to construct theory and a political agenda for achieving social justice rather than only engaging in intellectual debates that deconstruct existing paradigms. Professor Dillard is part of a cadre of feminist writers who advocate radical changes in the academy to eradicate educational inequity.     

Analysis of a Quasi-Experimental Design Based on Environmental Problem Solving for the Initial Training of Future Teachers of Environmental Education

Abstract

Many parameters may be used to measure the deterioration of water quality. One very important parameter is total dissolved solids (TDS). An increase in TDS beyond acceptable levels can have a significant impact on municipal, industrial, and agricultural use of water. In this review an overview of the problem of high TDS levels is given. Factors related to TDS which are considered include: (a) laboratory determination, (b) natural and man-influenced sources, (c) adverse effects, and (d) treatment process removal techniques. A brief summary of the TDS problem associated with the Colorado River is also considered.     

Lifelong learning in public libraries in 12 European Union countries: issues in monitoring and evaluation

Public libraries in Europe have supported lifelong learning for the past 500 years. Since the Lisbon Strategy emphasized the role of lifelong learning in economic policy, public libraries have been repositioning their services to respond to this new context. In some cases, these roles are undertaken with limited legislative or strategic changes and stagnant levels of funding. As a result, the sector receives little recognition of its role in lifelong learning amongst policy-makers. A consortium representing 12 EU countries, ENTITLE, was formed to increase awareness of the role public libraries play in this area. It undertook a survey amongst its members to scope relevant policies, strategies and evaluation efforts. This paper presents an analysis of this survey. It shifts the focus away from debates about the instrumental value of libraries. Instead, it explores the role that evaluation plays in policy implementation. It argues that participatory evaluation can help reduce conflict and ambiguity amongst the stakeholders involved in delivering symbolic implementation of policies. So far, however, current evaluation efforts in most ENTITLE countries have played a limited role in supporting coordination and, for some countries, may in fact remove resources away from more effective development efforts, including pedagogical training.