Human runners exhibit a least variable gait speed

This study characterises the relationship between gait variability and speed in runners using data from trunk accelerations in each axis.

Twelve participants of varying fitness ran on the treadmill with three sessions of six randomly ordered self-selected speeds. A VO_2max test was conducted on the fourth session. Running gait was tracked with inertial sensors. The occurrence of a mid-range speed was analysed for the anterior–posterior, vertical and lateral directional coefficient of variation (CV) of root mean square (RMS) acceleration data.

One participant with noisy gait signals was omitted. The results show all remaining participants consistently showed significant quadratic U-shaped relationships between vertical RMS CV acceleration and speed. Neither anterior–posterior nor lateral RMS CV acceleration were clearly related to speed. These least variable gait speeds were similar to estimates of optimal speed derived from minimum cost of transport with speed.

In conclusion, there exists a mid-range speed for each runner with the least variable gait in the vertical direction, and this occurred significantly more often than would be expected by chance (P < 0.05). However, there are no prominent patterns for the anterior–posterior and lateral directions. This finding supports anecdotal evidence from runners and coaches concerning gait consistency.     

The experience of captaincy in professional sport: The case of elite professional rugby

The captain is perceived to be an important member of the leadership structure within teams across many professional sports. However, while there is a general acceptance that this is the case, there is very little research exploring the role and associated demands at an elite level. As a result, the aim of this study was to explore the captaincy experiences of elite professional rugby union captains. The participants were eight male captains purposefully sampled for this study. Participants were interviewed individually to gain an understanding of each participant’s captaincy experiences. The data were thematically analysed using interpretative phenomenological analysis. Nine super-ordinate themes emerged in the study: role, skills, requirements, challenges, the coach, development, experience, context, and approach. Results suggest that the captaincy role is broader than previously highlighted, particularly at the elite level. Also, the study highlights inconsistencies in the selection of captains and a lack of formal developmental support for elite rugby captains. As a result, future research should explore the development of specific evidence-based approaches to captain selection and development.     

A meta-study of qualitative research examining stressor appraisals and coping among adolescents in sport

The main aim of this study was to create an integrated theoretical perspective of the qualitative adolescent sport stressor appraisal and coping literature. A secondary aim was to critique theoretical and methodological issues in the extant literature. Following database searches, 20 studies were retained for analysis. Meta-data, meta-theory, and meta-method analyses were conducted followed by a final meta-synthesis of findings. Analyses produced four themes: contextual and dynamic stressor appraisals, contextual and dynamic coping, coping resources and processes of acquisition, and social networks as assets and liabilities. Findings highlight the need for precise use of theory in the study of coping. Finally, while several data collection methods have been used, there is scope for greater methodological diversity to advance our understanding of coping among adolescent athletes.     

Developmental gender differences for overhand throwing in Aboriginal Australian children

In a review of 46 meta-analyses of gender differences, overhand throwing had the largest gender difference favoring boys (ES > 3.0). Expectations for gender-specific performances may be less pronounced in female Australian Aborigines, because historical accounts state they threw for defense and hunting. Overhand throwing velocities and kinematics were recorded in 30 female and male Aboriginal Australian children 6-10 years old. Results indicated the Aboriginal girls and boys were more similar in horizontal ball velocities than U.S. girls and boys. Throwing kinematics between girls and boys were also more similar in Australian Aborigines than U.S. children. Aboriginal girls threw with greater velocities than U.S., German, Japanese, and Thai girls, while the boys were similar across cultures.     

The special features of sport: A critical revisit

In the world of contemporary sport it is commonly claimed that at its elite end at least, sport's management is complex because the product it delivers to participants and fans is so idiosyncratic. This claim is accompanied by the view that while professional sport is in large part just another form of business, it has a range of special features that demand a customised set of practices to ensure its effective operation. This article aims to re-examine this view in the light of sport's commercial and socio-cultural developments over the last decade. It initially proposes that while both business and sport are concerned with widening market share, building profits, and strengthening brands, the presumption that sport has a monopoly over the delivery of intense emotional experiences, tribal belonging, and strong interpersonal relationships, is difficult to defend. The article concludes that while sport's economic and social progress has created an industry that is built around complex bureaucracies that turn over many thousands of millions of dollars every year, it has also created a more diverse and heterogeneous system of structures and experiences that are difficult to conflate to a handful of neat special features.     

Mapping undergraduate chemistry students' epistemic ideas about models and modeling

Developing and using scientific models is an important scientific practice for science students. Undergraduate chemistry curricula are often centered on established disciplinary models, and assessments typically provide students with opportunities to use these models to predict and explain chemical phenomena. However, traditional curricula generally provide few opportunities for students to consider the epistemic nature of models and the process of modeling. To gain a sense of how introductory chemistry students understand model changeability, model multiplicity, the evaluation of models, and the process of modeling, we use a construct-mapping approach to characterize the sophistication of students' epistemic knowledge of models and modeling. We present a set of four related construct maps that we developed based on the work of other scholars and empirically validated in an undergraduate introductory chemistry setting. We use the construct maps to identify themes in students' responses to an open-ended survey instrument, the models in chemistry survey, and discuss the implications for teaching.     

Evaluating the usability and instructional design quality of Interactive Virtual Training for Teachers (IVT-T)

Educational technology research and development - Simulation offers unique affordances over traditional training (e.g., remote access, mastery learning experiences, immediate feedback) relevant to...     

“Sprouting” the Couch Potato: Techniques to Increase the Effort Learners Invest in Video-Based Materials

Although videotapes are a popular instructional medium in the training environment, viewers often adopt a passive stance toward learning from video. Viewers perceptions of video as a passive, “easy” medium may minimize the information they gain from video-based instruction. If instructional designers and trainers want to encourage the “couch potato” to process the content of a video-based lesson in an active manner, they should make sure that their lessons are designed to facilitate this process. This article discusses the relationship of mental effort to achievement, provides recommendations for designing video-based materials to increase the effort learners invest in the instruction, and presents a list of practical techniques for increasing learners' mental effort and achievement that can be incorporated into lessons that include video-based materials.