Measurement procedures affect the interpretation of metatarsophalangeal joint function during accelerated sprinting

Abstract

The metatarsophalangeal joint (MPJ) is a significant absorber of energy in sprinting. This study examined the influence of MPJ axis choice and filter cut-off frequency on kinetic variables describing MPJ function during accelerated sprinting. Eight trained sprinters performed maximal sprints along a runway. Three-dimensional high-speed (1000 Hz) kinematic and kinetic data were collected at the 20 m point. Three axis definitions for the five MPJs were compared. MPJ moments, powers and energies were calculated using different filter cut-off frequencies. The more anatomically appropriate dual axis resulted in less energy absorbed at the MPJ compared to the oblique axis which also absorbed less energy compared to the perpendicular axis. Furthermore, a low cut-off frequency (8 Hz) substantially underestimated MPJ kinematics, kinetics and the energy absorbed at the joint and lowered the estimate of energy production during push-off. It is concluded that a better understanding of MPJ function during sprinting would be obtained by using an oblique or anatomically appropriate representation of the joint together with appropriate kinematic data sampling and filtering so that high frequency movement characteristics are retained.     

Effects of upper and lower body wearable resistance on spatio-temporal and kinetic parameters during running

ABSTRACT

Wearable resistance training involves added load attached directly to the body during sporting movements. The effects of load position during running are not yet fully established. Therefore, the purpose of this research was to determine spatio-temporal and kinetic characteristics during submaximal running using upper, lower and whole-body wearable resistance (1–10% body mass (BM)). Twelve trained male runners completed eight 2-min treadmill running bouts at 3.9 m/s with and without wearable resistance. The first and last bouts were unloaded, while the middle 6 were randomised wearable resistance conditions: upper body (UB) 5% BM, lower body (LB) 1%, 3%, 5% BM and whole body (WB) 5%, 10% BM. Wearable resistance of 1–10% BM resulted in a significant increase in heart rate (5.40–8.84%), but minimal impact on spatio-temporal variables. Loads of 5% BM and greater caused changes in vertical stiffness, vertical and horizontal force, and impulse. Functional and effective propulsive force (2.95%, 2.88%) and impulse (3.40%, 3.38%) were significantly (p < 0.05) greater with LB5% than UB5%. Wearable resistance may be used to increase muscular kinetics during running without negatively impacting spatio-temporal variables. The application of these findings will vary depending on athlete goals. Future longitudinal studies are required to validate training contentions.     

Technology and Early Childhood Education: A Technology Integration Professional Development Model for Practicing Teachers

Despite the promise of technology in education, many practicing teachers are faced with multiple challenges of effectively integrating technology into their classroom instruction. Additionally, teachers who are successful incorporating educational technology into their instruction recognize that although technology tools have the potential to help children, they are not ends in themselves. This article describes a Summer Institute project that the authors facilitated in a medium sized midwest public university. The summer workshop afforded participating early childhood education teachers exciting opportunities to interact with various instructional tools and technology applications. Further, the practicing teachers explored various strategies to integrate specific technology tools into their lessons in a manner consistent with constructivist pedagogy. This article is intended to stimulate reflections on the need to adopt a suitable technology integration professional development model in early childhood education classrooms to support young learners.     

Publishing: a market-led approach

A definition of marketing is offered. Detailed analysis demonstrates the editorial and commercial benefits of a market-led approach to publishing.     

Educational workshop improved information-seeking skills,knowledge, attitudes and the search outcome of hospital clinicians: a randomised controlled trial

A double-blind randomised controlled trial was conducted on a group of Hong Kong hospital clinicians. The objective was to test if a three-hour educational workshop (with supervised hands-on practice) is more effective (than no training) to improve clinical question formulation, information-seeking skills, knowledge, attitudes, and search outcomes. The design was a post-test-only control group; recruitment by stratified randomization (by profession), blocked at 800. End-user training was more effective than no training in improving clinical question formulation, in raising awareness, knowledge, confidence and use of databases, but had made no impact on preference for secondary databases. It changed the attitude of clinicians to become more positive towards the use of electronic information services (EIS). Participants had higher search performance and outcomes (satisfaction with information obtained (NNT = 3), EIS satisfaction (NNT = 3) and success in problem solving (NNT = 4)). The workshop improved knowledge and skills in evidence-based searching, but this effect gradually eroded with time. Search logs confirmed that follow-up is required if effects are to be sustained. Longer effects on search behaviours appear to be positive. A randomised controlled trial is valuable in identifying cause-and-effect relations and to quantify the magnitude of the effects for management decision-making.     

Geography,the Academy and Libraries

Geographic information sources have evolved at the same rate as the many other information sources in the last half a century. This article discusses geographic literacy and spatial thinking, and the questions that derive from geographic inquiry. Librarians in academic libraries are most often called on to meet the complex specialized geographic information needs that arise from study and practice in those areas. The sources we use and the ways we respond to these needs have evolved and expanded with the advent of various digital technologies. In order to be able to work with these new technologies, librarians can develop specialized competencies in geographic information systems (GIS) which allow them to go beyond print maps and atlases in the provision of geographic information.     

The U.S. Military Veteran in News Photographs: Representation and Stereotypes

Commenters have expressed concern over media content related to military veterans, saying journalists fail to provide the public with an accurate understanding of what it means to be a veteran. Nevertheless, few studies have examined the representation of veterans in news media content. The present study analyzed 740 photographs shared by regional news outlets on the popular social media platform Twitter. Coders documented the representation of veteran groups (gender, race, and service period) and stereotypes concerning veterans (homelessness, charity, and trauma) in the images. Results showed that the photographs rarely communicated stereotypes about veterans. Photographs overrepresented female veterans, although male veterans remained the significant majority. Minority veterans were underrepresented. Photographs most often contained images associated with World War II.