Sex differences in elbow and wrist joint loading during the cartwheel and round off with different hand positions performed by young gymnasts

The aim of the study was to determine if sex differences exist in the key elbow and wrist joint injury risk factors during different cartwheel (CW) and round-off (RO) techniques performed by young male and female artistic gymnasts. Sixteen active young gymnasts (8 males and 8 females) performed 30 successful trials of CW and RO with three different hand positions (parallel (10), T-shape (10) and reverse (10)). Synchronised kinematic and kinetic data were collected for each trial. Two-way repeated measures ANOVA (3 × 2, technique × sex) and effect-sizes (ES) were used for statistical analysis. In conclusion, female gymnasts exhibited greater normalised peak vertical ground reaction forces (VGRF), elbow and wrist compression forces and elbow internal adduction moments during CW and RO skills compared with male gymnasts. In both sexes, the parallel and reverse techniques increased peak VGRF, elbow and wrist compression forces and the elbow internal adduction moment. Increased elbow flexion resulted in decreased peak VGRF, elbow compression forces and elbow internal adduction moment. Injury risk factors including elbow extension and internal adduction moment with axial compression force suggest that a CW and RO in reverse and parallel techniques can be hazardous especially for young female gymnasts.     

Key somatic variables in young backstroke swimmers

The purpose of this study was to estimate the optimal body size, limb-segment length, girth or breadth ratios for 100-m backstroke mean speed performance in young swimmers. Sixty-three young swimmers (boys [n = 30; age: 13.98 ± 0.58 years]; girls [n = 33; age: 13.02 ± 1.20 years]) participated in this study. To identify the optimal body size and body composition components associated with 100-m backstroke speed performance, we adopted a multiplicative allometric log-linear regression model, which was refined using backward elimination. The multiplicative allometric model exploring the association between 100-m backstroke mean speed performance and the different somatic measurements estimated that biological age, sitting height, leg length for the lower-limbs, and two girths (forearm and arm relaxed girth) are the key predictors. Stature and body mass did not contribute to the model, suggesting that the advantage of longer levers was limb-specific rather than a general whole-body advantage. In fact, it is only by adopting multiplicative allometric models that the abovementioned ratios could have been derived. These findings highlighted the importance of considering somatic characteristics of young backstroke swimmers and can help swimming coaches to classify their swimmers and enable them to suggest what might be the swimmers’ most appropriate stroke (talent identification).     

The ‘aggressive style’: genesis of an ambiguous resource for Swiss hockey and football players

In this study, we investigated what drives players to endorse an aggressive style in Swiss ice hockey and football. We selected a sample of 16 players on the basis of their penalty statistics. We used semi-directed retrospective interviews to collect players’; biographic narratives. The results show a socialization process into an aggressive style, supported by the dominant gender and socialization norms of the sport, which is under the influence of the structure of the sports organization. However, there are large differences between players, with only some of them adopting an aggressive style. Although many studies have underlined the influence of moral disengagement, the present results suggest that time also matters and that the diversity of career paths may explain the diversity in attitudes. Socialization differences in the sports field, bodily capital, a career path marked by thwarted reputation are the key factors that drive players to adopt an aggressive style.     

Inter-segmental coordination in progressions for the longswing on high bar

This study focused on identifying the most effective skill progression for developing the longswing on high bar in men's artistic gymnastics. Building on previous work by Irwin and Kerwin, in which a method to rank progressions based on their angular kinematics was developed, this study aimed to use the method to quantify similarities in inter-segmental coordination between selected progressions and the longswing on high bar. Video images of four members of the UK men's national gymnastics squad performing three series of five longswings and eight progressions were recorded at 50Hz. Two-dimensional direct linear transformation techniques were used to determine the real-world coordinates from the digitized data. Inter-segmental coordination of the hip and shoulder joints during the functional phases of the longswing was assessed using continuous relative phase. Similarity between the longswing and each progression was represented by a "specificity score", which was also used to rank the progressions. Each progression's specificity score was calculated by combining a "difference score" (root mean squared difference between the continuous relative phase profiles of the longswing and the progression) and a "variability score" (standard deviation of the continuous relative phase profiles for each progression). The progressions that were most similar to the longswing included the looped bar longswing and layaway swing down (ranked 1st and 2nd), with specificity scores of 9% and 10% respectively. In contrast, the least similar progressions were the looped bar "no action" longswing (51%) and pendulum swing (63%) (ranked 7th and 8th). Establishing effective skill learning pathways is recognized as a key component of the coaching process and ranking progressions based on their specificity score provided a mechanism to identify progressions with similar inter-segmental coordination profiles to the key skill on the high bar, the longswing.     

Factors contributing to preservice teachers' management of children's problem behaviors

The purpose of this study was to assess factors that contribute to preservice teachers' choice of a helping or a restrictive strategy to manage social immaturity and social defiance behaviors among children. Levels of tolerance, opinions as to the causes of behavior, perceptions of adverse effects or costs of problem behaviors, and choice of strategy were measured in response to hypothetical samples of problem behavior. Regression analyses indicated that the costs of problem behavior significantly predicted the type of strategy that would be chosen. Training preservice teachers to manage these costs was the main implication for teacher training programs.     

Transformation and job creation in the cultural and creative industries in South Africa

The cultural and creative industries (CCIs) have been hailed as offering great potential to create jobs and to be socially inclusive. Since artistic success is defined by individual talent, or merit, the CCIs should be one sector that is especially open to, and appreciative of, social diversity in terms of race, class, cultural group and gender. However, as expected, recent studies in both the UK and the US have revealed that employment in the CCIs is heavily dominated by the middle classes, and is not as diverse in terms of other characteristics. Since the advent of democracy in South Africa in 1994, transformation of firm ownership, previously dominated by white people, to include more black, coloured and Indian/Asian-origin South Africans, has been an important part of achieving greater economic equality and social cohesion, as well as being more representative of the cultures of the majority of the population. Using data from a survey of 2400 CCIs firms in South Africa, this paper examines the extent to which the CCIs in South Africa have transformed in terms of ownership and employment. Comparisons are also made across the six UNESCO [(2009). Framework for cultural statistics. UNESCO Institute for Statistics. Retrieved from http://www.uis.unesco.org/culture/Pages/framework-cultural-statistics.aspx] “Cultural Domains” in terms of ownership, average monthly turnover and the number of full-time, part-time and contract employees. Results show some diversity in the industry, but significant differences between the Domains. Statistical analysis demonstrates that CCI funding policy in South Africa is sensitive to advancing the transformation agenda in that more transformed firms were shown to be more likely to have received some form of government grant as part of their income.     

Validity and Reliability of Three Self-Report Instruments for Assessing Attainment of Physical Activity Guidelines in University Students

The purpose of this study was to compare the validity and reliability of three short physical activity self-report instruments to determine their potential for use with university student populations. The participants (N = 155; 44.5% male; 22.9 ± 5.13 years) wore an accelerometer for 9 consecutive days and completed a single-item measure, the a brief two item measure and the International Physical Activity Questionnaire—Short Form questionnaires on day 1 and 9. Correlations between self-reported and accelerometer derived moderate-to-vigorous physical activity levels were moderate for the International Physical Activity Questionnaire—Short Form, while poor for the single-item measure and the a brief two item measure. The agreement level was high with the International Physical Activity Questionnaire—Short Form (77.4%) and moderate for both the single-item measure (45.2 %) and a brief two item measure (44.5 %). The intraclass correlations between the two administrations were moderate to strong across all measures (0.52–0.70) in 133 participants. The International Physical Activity Questionnaire—Short Form is the most suitable of these three self-report instruments for use with this population due to higher correlations and levels of agreement with accelerometry.     

A brief screening battery for predicting school achievement at ages seven and nine years

This article describes the development, utilization, and evaluation of an early screening battery for predicting school success or failure. The battery was administered to the pediatric population of the Southern California Permanente Medical Group, Panorama City Medical Center, at the time of the routine five-year health examination. For 411 children whose school performance was assessed by the teacher at age seven years, the Caldwell Test was the best predictor, but it had significant value for girls only (p<0.0001). In 1,251 children evaluated at age nine years, the Beery-Butkenica Developmental Test of Visual-Motor Integration (VMI) and the Caldwell Test were the best predictors (p⩽0.003). In 600 children for whom we had teacher ratings at ages seven and nine years, the VMI repeated at age seven years significantly predicted academic achievement and reading at age nine years for girls and boys (p = 0.007). Although combining the academic performance with VMI results at age seven years yielded 89% accuracy of prediction at age nine years, the false-positive rate represents a serious practical problem of mislabeling children as school failures.