Cardiac Dimensions in Elite Young Track Athletes

The purpose of the study was to compare young sprint and distance runners for changes in their cardiac dimensions with increased age (10–17 years) or body surface area (1–2 m²). Echocardiographic dimensions were obtained on 73 male track athletes competing in the 1983 National Age Group Track and Field Association championships. Each group of athletes was also compared with a hypothetical normal population (matched for weight and age) generated from prediction equations derived by Henry, Gardin, & Ware (1980). The cardiac dimensions examined were: Left ventricular internal diameter, left ventricular posterior wall thickness, and interventricular septum thickness. The male distance runners (n = 38) had a significantly greater increase in left ventricular posterior wall thickness and interventricular septum thickness with increasing age or increasing body surface area compared to the sprinters (n = 35) or compared to the predicted normal population. The left ventricular internal diameter was not significantly different between the groups. These results indicate that the hearts of male distance runners are undergoing a training hypertrophy whereas the hearts of sprinters are no different than hearts in a normal population. The changes in cardiac dimensions of these young athletes run counter to the generalizations stated for adult athletes: That endurance training enlarges the left ventricular internal diameter, but does not increase the left ventricular posterior wall or interventricular septum thickness.     

Dispositions of elite-level Australian rugby coaches towards game sense: characteristics of their coaching habitus

Bourdieu's analytic concept of habitus has provided a valuable means of theorising coach development but is yet to be operationalised in empirical research. This article redresses this oversight by drawing on a larger study that inquired into how the ‘coaching habitus’ of elite-level Australian and New Zealand rugby coaches structured their interpretation and use of the Game Sense approach to coaching to illustrate how habitus can be operationalised. It focuses on the identification of characteristics of the individual coaching habitus of four elite-level Australian rugby coaches and how they shape their interpretation and use of Game Sense. Drawing on suggestions made by Lau, we identify the characteristics of four individual ‘coaching habitus’ by examining their views on: (1) the characteristics of good coaches; (2) characteristics of great rugby players and how to develop them; and (3) their dispositions towards innovation in coaching.     

Baseball

The purpose of this study was to quantify and compare kinematic, temporal, and kinetic characteristics of American and Korean professional pitchers in order to investigate differences in pitching mechanics, performance, and injury risks among two different cultures and populations of baseball pitchers. Eleven American and eight Korean healthy professional baseball pitchers threw multiple fastball pitches off an indoor throwing mound positioned at regulation distance from home plate. A Motion Analysis three‐dimensional automatic digitizing system was used to collect 200 Hz video data from four electronically synchronized cameras. Twenty kinematic, six temporal, and 11 kinetic variables were analyzed at lead foot contact, during the arm cocking and arm acceleration phases, at ball release, and during the arm deceleration phase. A radar gun was used to quantify ball velocity. At lead foot contact, the American pitchers had significantly greater horizontal abduction of the throwing shoulder, while Korean pitchers exhibited significantly greater abduction and external rotation of the throwing shoulder. During arm cocking, the American pitchers displayed significantly greater maximum shoulder external rotation and maximum pelvis angular velocity. At the instant of ball release, the American pitchers had significantly greater forward trunk tilt and ball velocity and significantly less knee flexion, which help explain why the American pitchers had 10% greater ball velocity compared to the Korean pitchers. The American pitchers had significantly greater maximum shoulder internal rotation torque and maximum elbow varus torque during arm cocking, significantly greater elbow flexion torque during arm acceleration, and significantly greater shoulder and elbow proximal forces during arm deceleration. While greater shoulder and elbow forces and torques generated in the American pitchers helped generate greater ball velocity for the American group, these greater kinetics may predispose this group to a higher risk of shoulder and elbow injuries.     

Kinematic and electromyographic comparisons between chin-ups and lat-pull down exercises

The purpose of this study was to compare kinematics and muscle activity between chin-ups and lat-pull down exercises and between muscle groups during the two exercises. Normalized electromyography (EMG) of biceps brachii (BB), triceps brachii (TB), pectoralis major (PM), latissimus dorsi (LD), rectus abdominus (RA), and erector spinae (ES) and kinematics of back, shoulder, and seventh cervical vertebrae (C7) was analysed during chin-ups and lat-pull down exercises. Normalized EMG of BB and ES and kinematics of shoulder and C7 for chin-ups were greater than lat-pull down exercises during the concentric phase (p < 0.05). For the eccentric phase, RA during lat-pull down exercises was greater than chin-ups and the kinematics of C7 during chin-ups was greater than lat-pull down exercises (p < 0.05). For chin-ups, BB, LD, and ES were greater than PM during the concentric phase, whereas BB and LD were greater than TB, and LD was greater than RA during the eccentric phase (p < 0.05). For lat-pull down exercise, BB and LD were greater than PM, TB, and ES during the concentric phase, whereas LD was greater than PM, TB, and BB during the eccentric phase (p < 0.05). Subsequently, chin-ups appears to be a more functional exercise.     

Risk factors for a New Zealand sample of sexually abusive children and adolescents

OBJECTIVE: The aim was to understand variables contributing to the occurrence of sexual offending in children and adolescents. METHOD: Twenty youngsters who had engaged in coercive sexual behavior involving other children were compared to a matched group of clinic-referred youngsters with conduct disorders. Assessments included family histories, interviews, and psychometric measures. RESULTS: There was no group difference in the frequency of experiencing sexual abuse. However, sexually abusive youngsters were more often exposed to adult caregivers with known histories of being sexually abusive. These children had been subjected to multiple distortions of adult attachment, tended to internalize distress, and failed to use available social supports. They were likely to have experienced physical and verbal abuse; children with behavior disorders were more likely to have a parent with a psychiatric illness and to have experienced parental conflict. CONCLUSION: Severely disrupted attachment, in conjunction with family experiences of inappropriate sexual expression, place children and adolescents at risk for sexual offending. Sexually abusive youngsters had less social supports and their offending occurred after a negative emotional experience, when there was opportunity in the form of younger victims. The study suggests an interaction among developmental pathways, coping skills, and immediate proximal variables for the perpetration of sexual abuse by young people.     

Impressions of ICOTS II

The following short contributions are from people who attended the Second International Conference on Teaching Statistics held in Victoria, August 1986     

A Principled Pedagogy for Religious Educators

Abstract

Drawing on whiteness literature and over fifty years of combined classroom instruction experience, two professors of race and religion—one black, one white—at predominantly white institutions, answer the question, “How do we as religious educators effectively teach white students to challenge racially distorted assumptions and promote racially just outcomes?” In reply, they call into question the idea of “safe space,” dissect “the white gaze,” and offer three pedagogical principles for preparing white students to be allies in antiracist struggle: principled dislocation, supportive relocation, and sustained cultivation.     

Overview of innovations in organization for learning

Five approaches to organization for learning are reviewed: student grouping practices, nongrading, individualizing instruction, departmentalization in the elementary school, and cooperative teaching. The review relates these approaches to the accomplishment of eight basic instructional aims in the cognitive and affective areas. The critical review of each type of organizational plan considers problems of design, implementation, and evaluation. The general conclusion reached is that, while several of the approaches hold considerable promise for improving instruction, there usually are serious shortcomings in program design and implementation that prevent determining their potential contributions.

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Résumé Cinq voies d'accès à l'organisation de l'instruction sont passées en revue: techniques de groupement d'élèves, non-gradation, instruction individualisante, mise en départements en école élémentaire, et enseignement co-opératif. L'étude rapporte ces approches à l'accomplissement de huit buts fondamentaux d'instruction sur les plans cognitifs et affectifs. L'examen critique de chaque type de plan d'organisation considère les problèmes de dessin, d'exécution, et d'évaluation. La conclusion générale atteinte est, bien que plusieurs approches s'annoncent très bien pour améliorer l'instruction, on trouve presque toujours de sérieux défauts dans le dessin et l'exécution des plans d'études qui empêchent de définir leur apport potentiel.

     

Agencies,educators, communities and wildfire: partnerships to enhance environmental education for youth

We studied seven programs that engage youth from 10 to 18 years old in wildfire risk reduction in their communities in the United States through in-depth interviews to examine the nature and role of community-school partnerships in resource-focused environmental education. While the programs use a variety of strategies, from Scout badge to summer school, they exhibit several common dimensions: they all engage youth in community projects; they all arise from partnerships between resource agencies, community organizations, and educators; they all began when people familiar with both wildfire and youth education saw an opportunity to improve the community and educate youth through action; and all partners are able to contribute to the common program yet retain their individual identity as they meet their own mission-based goals. We use themes and quotes to illustrate these common dimensions for establishing community-school partnerships that could build action competence through environment-based education projects.