The effect of video-feedback on the learning of the tennis service by intermediate players

Effects of video-feedback on improvement of the tennis service were investigated in subjects having at least 2 years of playing experience in tennis. The experiment was carried out in an indoor tennis hall under normal training conditions. Subjects were randomly divided into three groups: a video-feedback training (VFT) group, a traditional training (TT) group and a control group, each consisting of 22 subjects. While the subjects of the control group received no training at all, subjects in both the VFT and TT groups were trained twice weekly during 5 consecutive weeks. Each training session lasted 40 min, of which 30 min was spent on actual practice in training of the service. The remaining 10 min was spent on watching, analysing and discussing video recordings of either their own service performed during the training session (VFT group), or ground strokes and volleys of top level players (TT group). Both the VFT and TT group showed significantly greater improvements in both achievement scores and form (technique) scores than did the control group. No differences, however, could be demonstrated between the VFT and TT group, indicating that the subjects of the former group did not benefit from the video-feedback they received. While form scores correlated significantly (P less than 0.001) with the velocity of the served ball, no such relation between form scores and spatial accuracy was apparent.     

Development of a grinding-specific performance test set-up

Abstract

The aim of this study was to develop a performance test set-up for America's Cup grinders. The test set-up had to mimic the on-boat grinding activity and be capable of collecting data for analysis and evaluation of grinding performance. This study included a literature-based analysis of grinding demands and a test protocol developed to accommodate the necessary physiological loads. This study resulted in a test protocol consisting of 10 intervals of 20 revolutions each interspersed with active resting periods of 50 s. The 20 revolutions are a combination of both forward and backward grinding and an exponentially rising resistance. A custom-made grinding ergometer was developed with computer-controlled resistance and capable of collecting data during the test. The data collected can be used to find measures of grinding performance such as peak power, time to complete and the decline in repeated grinding performance.     

Narrating Your Work: an approach to supporting knowledge sharing in virtual teams

We propose an approach to enhancing knowledge sharing and connectedness in distributed teams. Termed ‘Narrating Your Work’ (NYW), the approach involves members of distributed team using a microblogging tool to post regular updates about their current work, accomplishments, and issues. The NYW approach was evaluated within a geographically and temporally distributed team at Shell International for a period of one month, using a mixed-method research design. Methodology comprised of a quantitative survey, followed by semi-structured interviews and analysis of microblogging updates posted during the month in which the approach was being trialled. The evaluation results suggest that NYW was viewed as a valid and practical approach to enhancing knowledge sharing and connectedness. A range of barriers and enablers that could impact the future application and embedding of the approach are identified and recommendations for implementation are outlined.     

Building Your Licensing and Negotiation Skills Toolkit

Licensing and the negotiating of electronic resources can be a daunting task for librarians who lack the proper skill sets and are unfamiliar with the intricacies of publisher agreements. Claire Dygert broke down the individual elements of a standard licensing agreement and explained the importance of protecting the rights of libraries. By providing insight from her years of experience, librarians learned how to develop a support network, build confidence, and be more effective negotiators.     

Wearable inertial sensors in swimming motion analysis: a systematic review

The use of contemporary technology is widely recognised as a key tool for enhancing competitive performance in swimming. Video analysis is traditionally used by coaches to acquire reliable biomechanical data about swimming performance; however, this approach requires a huge computational effort, thus introducing a delay in providing quantitative information. Inertial and magnetic sensors, including accelerometers, gyroscopes and magnetometers, have been recently introduced to assess the biomechanics of swimming performance. Research in this field has attracted a great deal of interest in the last decade due to the gradual improvement of the performance of sensors and the decreasing cost of miniaturised wearable devices. With the aim of describing the state of the art of current developments in this area, a systematic review of the existing methods was performed using the following databases: PubMed, ISI Web of Knowledge, IEEE Xplore, Google Scholar, Scopus and Science Direct. Twenty-seven articles published in indexed journals and conference proceedings, focusing on the biomechanical analysis of swimming by means of inertial sensors were reviewed. The articles were categorised according to sensor’s specification, anatomical sites where the sensors were attached, experimental design and applications for the analysis of swimming performance. Results indicate that inertial sensors are reliable tools for swimming biomechanical analyses.