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.     

Near-infrared spectroscopy-derived total haemoglobin as an indicator of changes in muscle blood flow during exercise-induced hyperaemia

ABSTRACT

Blood flow changes in response to exercise have been attributed, among other factors, to the effect of vasodilators factors on the microvasculature, suggesting a close relationship between small blood vessels and conducting arteries. The main purpose of this study was to determine the relationship between the changes in near infrared spectroscopy (NIRS)-derived total haemoglobin ([tHb]) and muscle oxygen saturation (SmO₂) signals and femoral artery blood flow in response to resistance exercise at fast- and slow-velocity muscle contraction. The study randomised crossover design included twelve participants. NIRS and blood flow measurements were continuously monitored before, during, and 5 min after the exercise protocol. There was a significant correlation between [tHb] reperfusion slope ([tHb]_slope) and peak blood flow (BF_peak) after slow- and fast-velocity muscle contraction (r = 0.83, p = 0.0008 and r = 0.72, p = 0.0080, respectively). No significant correlation existed between the SmO₂ reperfusion slope (SmO_{2_slope}) and BF_peak after both slow- and fast-velocity muscle contraction exercise (r = ?0.46, p = 0.1253 and r = 0.33, p = 0.2841, respectively). This study demonstrated a strong relationship between the NIRS-derived [tHb] and Doppler ultrasound BF during the recovery period of dynamic resistance exercise at both slow- and fast-velocity contraction.     

REEARCH REPORT

This paper addresses the concept of geological time as used by students who face tasks that demand three types of skills: to locate events in time, to order them according to time calendar, and to manage time intervals. The empirical study consisted of asking high school students as well as technical school students to carry out tasks that required the use of the three previously mentioned components. It was found, first, that students frequently used erroneous temporal labels, which shows a lack of knowledge that would allow them to locate events within the context of geobiologic data. Second, the students did not store the representation of a succession of events, but were nevertheless able to create it by means of the deductive use of previous knowledge. Finally, the importance of having an appropriate representation of geological time intervals became patent while observing the students' difficulties in understanding geologic changes.     

Estrategias de conteo implicadas en los procesos de adición y sustracción

Resumen

A lo largo del presente trabajo se analizan las diferencias existentes entre los diversos procesos puestos en juego por los sujetos a la hora de cuantificar lo real, destacando de entre ellos el subproceso de cuantificación extensiva métrica y uno de los esquemas básicos que lleva aparejados: el esquema de conteo. A continuación se pasa a analizar las diferentes estrategias utilizadas por nuetros escolares de 1°, 2°, 3° y 4° de E.G.B. cuando aplican este esquema para la resolución de algoritmos de adición y de sustracción, destacando la vinculación entre el desarrollo de las estrategias de conteo y la eficiencia en la solución de estos algoritmos.     

Students' evaluation of CALL software programs

Although several studies have explored the attitudes of teachers and students towards CALL, there has been little research regarding students' insights and impressions. We agree with Kessler and Plakans (2001, p. 15) when they state that in the process of evaluating materials ‘learners must be included, as they are also experts of their learning as well as the benefactors of well‐developed materials’. With this in mind, we undertook a study in which students were given the opportunity to express their opinions about the software they used in the multimedia laboratory. The sample was made up of 59 undergraduates who completed a questionnaire. The conclusion to be drawn is that students clearly see software programs as a complementary tool in the foreign language classroom.Évaluation par les étudiants des programmes d'informatique. Bien que plusieurs études aient exploré les attitudes des enseignants et des enseignés envers le CALL, il y a eu peu de recherches sur les vues et impressions des étudiants. Nous sommes d'accord avec Kessler et Paklans (2001, p. 15) quand ils déclarent que dans le processus d'évaluation des documents les étudiants doivent être inclus car ils sont aussi experts de leur apprentissage aussi bien que les bénéficiaires de documents bien conçus! Dans cet esprit nous avons entrepris une étude dans laquelle les étudiants ont eu l'occasion d'exprimer leurs opinions sur le logiciel qu'ils utilisent dans le laboratoire multimédia. L'échantillon était constitué de 59 « undergraduates » qui ont rempli un questionnaire. La conclusion à en tirer est que les étudiants voient clairement ces logiciels comme un outil complémentaire dans la classe des langues étrangères.Evaluation von CALL Software Programmen durch Studenten. Obwohl verschiedene Studien die Einstellungen von Lehrern/Dozenten und Schülern/Studenten dem CALL-Programm gegenüber untersucht haben, ist bislang wenig über die Eindrücke und Erlebnisse der Schüler und Studenten geforscht worden. Wir stimmen mit Kessler und Plakans (2001, S 15) überein, wenn sie behaupten, dass man im Prozess der Evaluierung des Materials 'die Lerner einbeziehen sollte, da sie einerseits Experten ihres eigenen Lernprozesses sind und andererseits von gut entwickelten Materialien profitieren'. Dies berücksichtigend führten wir eine Studie durch, in der den Studenten die Gelegenheit gegeben wurde, ihre Meinungen über die Software, die sie im Multimedia-Labor nutzten, darzulegen. Die Stichprobe bestand aus 59 Studenten, die einen Fragebogen ausfüllten. Die Schlussfolgerung war, dass Studenten Softwareprogramme eindeutig als ergänzendes Werkzeug im Fremdsprachenunterricht betrachten.     

Inquiry projects for scientific education: a good option for compulsory secondary education / Proyectos de indagación para la educación científica: una buena opción para la educación secundaria obligatoria

The approach of learning science through inquiry presents significant challenges for teachers and students. In light of this, an extensive experience has been developed in which students without any previous training or specific interests have been organized into small groups to carry out scientific inquiry projects guided by their teachers. Evaluation of the experience is clearly positive, and is based on questionnaires completed at the end of the experience by the students as well as retrospective reports provided by their teachers. Despite this, some problems are presented, such as the difficulty or repetitiveness of some scientific practices mentioned by some students, or when the inquiry or the group does not work out in some cases, as mentioned by teachers. Scientific inquiry projects like the one described here could play a key role in science education in compulsory secondary education.     

葡萄牙基础教育数学课程标准述评

近年来,诸多国家关注数学课程改革,数学课程标准一再修订.在这样的国际背景下,葡萄牙教育部于2007年颁布了新的<基础教育数学课程标准>.本文主要介绍葡萄牙20世纪80年代以来的教育体制和标准制定的背景,并在阐述新标准结构和具体内容的基础上,分析了葡萄牙当前基础教育数学课程标准的特点,以资借鉴.     

Wage determinants among medical doctors and nurses in Spain

This paper examines the determination of wage rates for health professionals using three well known, and commonly used, econometric techniques: ordinary least squares, instrumental variables, and Heckman’s method. The data come from a graduate survey and the analysis focuses on a regional labor market, due to nationwide information on salaries is absent in Spain. After estimating different wage equations, the results suggest that OLS estimates are preferable. The findings show an important wage premium for medical doctors relative to nurses, but also a wage advantage for workers who are civil servants and a gender wage-gap that favors men. Although the expansion of higher education in Spain has reduced social inequalities in access, the main policy implication from this paper is that social class differences can still persist at the degree level—in the choice of degree—if students of higher socioeconomic status get a place at university in a degree of higher earnings, a fact that is corroborated in this study.