We Could be Heroes

Conor P. McLaughlin and Christopher B. Newman challenge us to use our power to create new possibilities for equity on our campuses.     

Childhood aerobic fitness predicts cognitive performance one year later

Abstract

Aerobically fit children outperform less fit peers on cognitive control challenges that involve inhibition, cognitive flexibility, and working memory. The aim of this study was to determine whether, compared with less fit children, more fit 9- and 10-year-old pre-adolescents exhibit superior performance on a modified compatible and incompatible flanker task of cognitive control at the initial time of fitness testing and approximately one year later. We found that more fit children demonstrated increased flanker accuracy at both test sessions, coupled with a superior ability to flexibly allocate strategies during task conditions that required different amounts of cognitive control, relative to less fit children. More fit children also gained a speed benefit at follow-up testing. Structural MRI data were also collected to investigate the relationship between basal ganglia volume and task performance. Bilateral putamen volumes of the dorsal striatum and globus pallidus volumes predicted flanker performance at initial and follow-up testing one year later. The present findings suggest that childhood aerobic fitness and basal ganglia volumes relate to cognitive control at the time of fitness testing and may play a role in cognitive performance in the future. We hope that this research will encourage public health and educational changes that will promote a physically active lifestyle in children.     

Threshold frequency of an electrically induced cramp increases following a repeated,localized fatiguing exercise

Abstract

Though clinical observations and laboratory data provide some support for the neuromuscular imbalance theory of the genesis of exercise-associated muscle cramps, no direct evidence has been published. The purpose of this study was to determine the effect of local muscle fatigue on the threshold frequency of an electrically induced muscle cramp. To determine baseline threshold frequency, a cramp was electrically induced in the flexor hallucis brevis of 16 apparently healthy participants (7 males, 9 females; age 25.1 ± 4.8 years). The testing order of control and fatigue conditions was counterbalanced. In the control condition, participants rested in a supine position for 30 min followed by another cramp induction to determine post-threshold frequency. In the fatigue condition, participants performed five bouts of great toe curls at 60% one-repetition maximum to failure with 1 min rest between bouts followed immediately by a post-threshold frequency measurement. Repeated-measures analysis of variance and simple main effects testing showed post-fatigue threshold frequency (32.9 ± 11.7 Hz) was greater (P < 0.001) than pre-fatigue threshold frequency (20.0 ± 7.7 Hz). An increase in threshold frequency seems to demonstrate a decrease in one's propensity to cramp following the fatigue exercise regimen used. These results contradict the proposed theory that suggests cramp propensity should increase following fatigue. However, differences in laboratory versus clinical fatiguing exercise and contributions from other sources, as well as the notion of a graded response to fatiguing exercise, on exercise-associated muscle cramp and electrically induced muscle cramp should be considered.     

New Frontiers in Visual Search: An Exploratory Study in Live Tennis Situations

This study compares the motor skills and physical fitness of school-age children (6-12 years) with visual impairments (VI; n = 60) and sighted children (n = 60). The relationships between the performance parameters and the children's body composition are investigated as well as the role of the severity of the impairment. The degree of VI did not differentially affect the outcomes. Compared to their sighted peers, the children with VI scored lower on the locomotor and object control skills as assessed with the Test of Gross Motor Development-2, and the physical fitness (Eurofit) parameters of plate tapping, the standing broad jump, the modified 5 × 10-m shuttle run, and 20-m multistage shuttle run (20-MST). Their body mass and body fat indexes were inversely correlated with the standing broad jump and the 20-MST, but positively correlated with handgrip strength. Moreover, significant inverse correlations were found between their locomotor and object control skills on the one hand and plate tapping and the 5 × 10-m shuttle run on the other hand. Given the relatively high proportion (25%) of overweight/obese children within the VI sample, educators are recommended to promote health-related activities and help enhance motor skills in this population.     

Methodological considerations for the 3D measurement of the X-factor and lower trunk movement in golf

It is believed that increasing the X-factor (movement of the shoulders relative to the hips) during the golf swing can increase ball velocity at impact. Increasing the X-factor may also increase the risk of low back pain. The aim of this study was to provide recommendations for the three-dimensional (3D) measurement of the X-factor and lower trunk movement during the golf swing. This three-part validation study involved; (1) developing and validating models and related algorithms (2) comparing 3D data obtained during static positions representative of the golf swing to visual estimates and (3) comparing 3D data obtained during dynamic golf swings to images gained from high-speed video. Of particular interest were issues related to sequence dependency. After models and algorithms were validated, results from parts two and three of the study supported the conclusion that a lateral bending/flexion-extension/axial rotation (ZYX) order of rotation was deemed to be the most suitable Cardanic sequence to use in the assessment of the X-factor and lower trunk movement in the golf swing. The findings of this study have relevance for further research examining the X-factor its relationship to club head speed and lower trunk movement and low back pain in golf.     

Alterations in kinematics and muscle activation patterns with the addition of a kipping action during a pull-up activity

Recently, addition of a gymnastics glide kip to a standard pull-up (SPU) has resulted in the kipping pull-up (KPU). Changes in muscle activation and kinematics were evaluated with eleven athletes performing sets of 5 SPU and 5 KPU. Surface electromyography of upper body and lower body muscles was recorded along with movement kinematics obtained via markers and motion tracking software. Most kinematic variables were significantly higher in the KPU including (KPU minus SPU deg): Max hip angle (48.8° ± 6.8°, p < 0.001) and max knee angle (56.5° ± 11.3°, p < 0.001). The recruitment of core and lower body muscles was significantly higher in the KPU (% MVIC increase): rectus abdominis (28.7 ± 4.7%, p < 0.001), external oblique (21.8 ± 4.1%, p < 0.001), iliopsoas (26.1 ± 5.5%, p = 0.001) and tensor fasciae latae (13.5 ± 2.3%, p < 0.001). Correspondingly, the biceps brachii had lower activation in the KPU (% MVIC decrease): (26.7 ± 0.6%, p = 0.006). Depending on the athlete’s goal, they may elect to perform an SPU for higher upper body muscle activation; or the KPU for more full-body activation with the potential to perform more repetitions through reduced upper body fatigue.     

The Significance of Gender Boundaries in Preadolescence: Contemporary Correlates and Antecedents of Boundary Violation and Maintenance

Previous research has established the importance of gender boundaries as a normative aspect of development in middle childhood. Here, the nature and importance of gender boundaries as an individual differences construct was explored. Ratings of gender boundary violation and gender boundary maintenance were made of 47 10–11-year-old children participating in a series of summer day camps. These ratings were supported by videotape-based behavior codings of gender boundary violating behaviors and by live observations of sheer number of associations with members of the opposite gender. In addition, considerable external validation of these individual differences was obtained. Children low on gender boundary violation and (especially) children high on boundary maintenance were independently judged by camp counselors to be socially competent. They also were found to be higher on a friendship variable, based on observation. Those who violated boundary were especially unpopular with peers, based on a child interview. Finally, boundary violation and maintenance were related to attachment history and to early measures of parent-child generational boundary distortions.     

The regulation of transnational higher education in Southeast Asia: Case studies of Hong Kong, Malaysia and Australia

The millennium round of the General Agreement on Tradein Services (GATS) underlines issues relating to the regulationof education as an internationally traded service. Transnationaleducation is a key component of such trade. Southeast Asia issomething of a laboratory in the development and regulation oftransnational education. The region combines high demand, keencompetition among providers, and host country regulatory regimesranging from relatively laissez faire to strongly interventionist.This paper examines the approaches of three Southeast Asiangovernments – Hong Kong, Malaysia and Australia – to theregulation of transnational education within their borders. Ineach case the authors provide background on the higher educationsystem, describe the regulatory approaches to transnationaleducation, and analyse the motivations behind regulation. Boththe neoliberal approach of the WTO to trade in educationalservices, and critiques of this approach, are outlined. Theauthors conclude that any attempts to promote global standards orquality principles for transnational education must address themyriad concerns of governments, including consumer protection,advancing national goals and protecting the local system.     

The Effect of an Analysis-of-Practice,Videocase-Based,Teacher Professional Development Program on Elementary Students' Science Achievement

This article describes the effects of an analysis-of-practice professional development (PD) program on elementary school students' (Grades 4–6) science outcomes. The study design was a cluster-randomized trial with an analysis sample of 77 schools, 144 teachers and 2,823 students. Forty-two schools were randomly assigned to treatment, (88.5 hours) of integrated analysis-of-practice and content deepening PD (over the course of one year) while 35 schools were randomly assigned to receive an equal number of PD hours in science content deepening alone. Students' content knowledge, as measured by a project-specific test, was compared across treatment groups. The effect size for this comparison was 0.52 standard deviations in favor of students whose teachers participated in the PD that included analysis-of-practice. This effect compares favorably to that of other elementary school interventions whose effectiveness was studied with a narrowly focused outcome measure. Analysis of the demographics of the study schools suggests that the treatment effect could be relevant outside the local study context. Implications for future research include tests of mediation for teacher-level outcomes and efficacy tests of specific teaching strategies (intervention subcomponents).