Segmental sequencing of kinetic energy in a computer-simulated golf swing

The concept of the transfer of kinetic energy (KE) sequentially through the human body from proximal to distal segments is an influential concept in biomechanics literature. The present study develops this area of research through investigation of segmental sequencing of the transfer of KE by means of computer simulation. Using a musculoskeletal computer model previously developed by the authors, driven using three-dimensional kinematic data from a single elite male golfer, combined inverse and forward dynamics analyses enabled derivation of KE. Rigid body segments of torso, hips, arms and clubhead were examined in line with previous literature. Using this method a driver swing was compared to a 7 iron swing. Findings showed a high level of correlation between driver and iron peak KE and timing of peak KE relative to impact. This seems to indicate equivalent trunk and arms linear velocity, thus force applied, for an iron shot and a driver shot. There were highly significant differences between KE output for body segments for both clubs. In addition, peak KE magnitudes increased sequentially from proximal to distal segments during swing simulations for both the driver and 7 iron. This supports the principle of the summation of speed. However, timing of peak KE was not sequential from proximal to distal segments, nor did segments peak simultaneously. Rather, arms peaked first, followed by hips, torso and club. This seems to indicate a subjective optimal coordination of sequencing.

Educational personnel's perceptions of mainstreaming and resource room effectiveness

Equivalent forms of a questionnaire were administered to elementary classroom and resource room teachers. The questionnaires were designed to elicit teachers' attitudes and perceptions as to the effectiveness and appropriateness of mainstreaming, regular classroom teachers' level of skill competency, assistance from the resource room, and communication between the resource room and regular classroom teachers. Results indicated that resource and regular teachers evidenced differential perceptions as to all factors investigated. Educational implications of the findings were discussed and specific recommendations were proposed.     

The effect of consistent and varied follow-through practice schedules on learning a table tennis backhand

In table tennis the follow-through action after a shot is an important part of skill execution. In this experiment, we aimed to extend literature around the contextual interference effect by investigating whether the way the follow-through is organised in practice affects learning of the backhand shot in table tennis. Thirty unskilled participants were allocated to blocked-variable practice, random-variable practice or a control-constant group and aimed backhand shots towards a target following ball projection from a machine. Each group completed these shots in a pre-test, a training phase with follow-through manipulations, a post-test, and a retention test. The random-variable group improved their shot accuracy from pre-test to post-test and from pre-test to retention test (both P < 0.01, d = 1.03), whereas neither the blocked-variable nor the control-constant group displayed any change in shot accuracy. Practising the follow-through in a random-variable fashion enhanced learning of the preceding shot compared with blocked-variable practice or no follow-through instructions. The benefits of learning motor skills under conditions of high contextual interference also apply to how follow-through actions are organised. The findings are valuable to coaches and suggest that instructions related to the follow-through action should be considered as well as the primary skill itself.     

Culturally biased voting in the Eurovision Song Contest: Do national contests differ?

The economic literature on the Eurovision Song Contest (ESC) establishes empirical evidence for culturally biased voting, more precisely also biases based on geographical closeness, political relations, ethnical and linguistic affinity. The Bundesvision Song Contest (BSC), a similar contest with principally the same rules but organized on the national level in Germany, offers a unique opportunity to compare international voting bias patterns to national voting bias patterns. Thus, this paper presents an innovative analysis by comparatively analyzing the ESC’s historical data from 1998 to 2014 and the BSC’s data from its beginning in 2005 until 2014 with the same econometric methodology. Our results show that voting biases do not only matter in international contests but also occur in similarly organized national contests with roughly similar magnitude and quality—despite the cultural background of participants and voters being much more homogenous.     

Exploring an activist approach of working with boys from socially vulnerable backgrounds in a sport context

This study explores an activist approach for co-creating a prototype pedagogical model of sport for working with boys from socially vulnerable backgrounds. This paper addresses the key features that emerged when we identified what facilitated and hindered the boys’ engagement in sport. This study was an activist research project that was conducted between July 2013 and December 2013 in a soccer program in a socially and economically disadvantaged neighborhood in Brazil. The lead author, supervised by the second author, worked with a soccer class of 17 boys between ages 13 and 15, 4 coaches, a pedagogical coordinator and a social worker. Multiple sources of data were collected, including 38 field journal/observations and audio records of: 18 youth work sessions, 16 coaches’ work sessions and 3 combined coaches and youth work sessions. In addition, the first and second author had 36 90-minute debriefing and planning sessions. By using an activist approach, three features were identified as being essential: an ethic of care, an attentiveness to the community and a community of sport. Findings suggest that it is possible to use sport as a cultural asset to benefit youth from socially vulnerable backgrounds by offering them a place where they can feel protected and dream about possible futures.     

Social support and physical activity participation among healthy adults: a systematic review of prospective studies

The objective of this review was to determine the direction and strength of the prospective relationship between social support and PA among healthy adults. A systematic review was conducted; including studies up until December 2015, in the following databases: Ovid MEDLINE, EMBASE, PsychINFO, SPORTDiscus, and Scopus. Published English and French written studies were included if the reported study used a longitudinal design; examined the relationship between social support and PA over at least two intervals; and assessed a sample of healthy adults between 18–65 years of age. Two reviewers independently extracted study information and independently assessed the risk of bias in each study. The initial search yielded a total of 2892 citations, and 20 studies were included in the review. Follow-up period ranged from 2 weeks to 10 years. Irrespective of the type and source of support, the strength and direction of the association between social support and PA was inconsistent across studies, with effect sizes ranging from small to large and from negative to positive. Based on meta-analysis, there was a small positive association between support for PA from friends and future PA. Researchers are encouraged to continue to conduct longitudinal studies to better understand the relationship between social support and PA.     

Female Workers,the Confectionery Industry,and the London Labour Market c.1880

This paper explores the labour conditions of a small confectionery firm, Epps and Co., in late Victorian London before the rise of New Unionism. Utilizing details of employees and disciplinary proceedings contained within a wage book uncovered in the Rowntree’s company archives, it explores how discipline was enacted in the complex world of the London labour market. The relationship between, employer, employee, and discipline placed significant emphasis on the individual rather than the group, and both employer strategy and employee resistance operated on a remarkably singular level.     

"The fouled player should not take the penalty himself": an empirical investigation of an old German football myth

In this study, we investigate the old German football myth that the fouled player should not take the resulting penalty himself, as he is at an increased risk of missing. Previous analyses are improved on as we adjust for potential confounders that might influence self-taking as well as successful penalty conversion. Our findings reveal some important predictors for self-taking but, somewhat surprisingly, neither self-taking nor any of the potential confounders predicts scoring a penalty kick.