The influence of shoe drop on the kinematics and kinetics of children tennis players

This study investigated the immediate effects of reducing the shoe drop (i.e. the difference between the heel and the forefoot height) on the kinematics and kinetics of the lower extremities of children tennis players performing a tennis-specific movement. Thirteen children tennis players performed a series of simulated open stance forehands wearing 3 pairs of shoes differing only in the drop: 0 (D0), 6 (D6) and the control condition of 12?mm (D12). Two embedded forceplates and a motion capture system were used to analyse the ground reaction forces and ankle and knee joint angles and moments of the leading lower limb. In D6 compared with D12, the peak impact force was reduced by 24% (p?=?.004) and the ankle was less dorsiflexed at foot strike (p?=?.037). In D0 compared with D12, the peak impact force was reduced by 17% (p?=?.049), the ankle was less dorsiflexed at foot strike (p?=?.045) and the knee was more flexed at foot strike (p?=?.007). In addition, 4 out of 13 participants (31%) presented a forefoot strike pattern for some of the trials in D0. No difference was observed across shoe conditions for the peak knee extensor moment (p?=?.658) or the peak ankle plantarflexor moment (p?=?.071). The results provide preliminary data supporting the hypothesis that for children tennis players, using a 6-mm lower shoe drop might reduce heel impact forces and thus limit potentially impact-related injuries.     

Why extraversion is not enough: the mediating role of initial peer network centrality linking personality to long-term academic performance

Academic performance (i.e., grade point average) determines career entry factors as well as career success and is thus crucial for students’ future careers. Besides individual factors such as personality traits, individuals’ social embeddedness has been shown to enhance performance. Regarding academic performance, relationships to fellow students (peers), which bundle into one’s developmental network, are a valuable source of psychosocial and career support because occupying central positions within a social network provides the benefit of being able to access career-enhancing resources. Integrating individual and social-contextual factors for the purpose of examining academic performance is therefore plausible. Research results indicate that personality, especially extraversion, might predict performance through network centrality. In this study, we examined this assumption by focusing on extraversion and centrality in the peer developmental network of recently acquainted German psychology bachelor students (N?=?47, 15% male). In a longitudinal design, we analyzed the impact of extraversion and centrality on students’ academic performance at the end of their studies. Results revealed that centrality (i.e., popularity) mediates the relationship of extraversion with academic performance, indicating that extraverted students (regardless of their agreeableness) are more popular among their peers, which, in turn, enhances their academic performance. That is, the likelihood of getting superior final grades depends on whether students manage to attract peers at the very beginning of their university life, which is easier for extraverts. These findings emphasize the importance of the social embeddedness of people, highlight its long-term effects on performance, and yield several implications for research and practice.     

Test-Based Learning: Inconsistent Effects Between Higher- and Lower-Level Test Questions

Providing test questions after an initial study phase is a common instructional technique. In theory, questions that require higher-level (deep) processing should be more beneficial than those that require lower-level (shallow) processing. However, empirical evidence on the matter is inconsistent. To shed light on two potential reasons for these inconsistencies, we conducted an experiment (N = 81) to analyze the role of (a) the share of information to which test questions direct learners and (b) the learning activities performed in the initial study phase with respect to the effects between higher- and lower-level test questions. We found that both the share of focused information and the initial learning activities moderated the effects between higher- and lower-level test questions.     

Community Consultation in Developing Museum Projects: A Case Study Using the Repertory Grid Technique

Good community consultation is a powerful tool in developing new museum projects and exhibitions, facilitating a more effective delivery of service to a diverse public. Existing techniques for both user and community consultation are limited with front end evaluation particularly undeveloped in the sector, often providing no meaningful base by which to compare project outcomes. Tension exists between government, which values quantitative data, and researchers who argue qualitative methods are more appropriate for evaluating community projects. This article reports a pilot study using the repertory grid technique to examine a ‘socially excluded’, ethnically diverse local community's perceptions, expectations and previous experiences of similar projects, to provide a benchmark against which to compare outcomes. This research formed part of the front end evaluation for a New Deal for Community's Project run by Sheffield Galleries and Museums Trust. The repertory grid technique was developed in psychological studies as a means of understanding respondents' own world views, and is particularly helpful in working with people with poor language skills. Although this study only used the technique qualitatively, it can be used to combine both quantitative and qualitative data, providing more robust data for evidence-based policy decisions. Using the repertory grid technique, respondents were able to list both perceived and practical barriers to participation in projects. The technique also enabled them to articulate what would motivate them to become involved in future projects. The repertory grid technique has significant potential for use in community consultation and project evaluation as a means of understanding local residents' perceptions and its visual representation means that its findings can be easily understood by participants, policy-makers and practitioners.     

Comparison of two Actigraph models for assessing free-living physical activity in Indian adolescents

This aim of this study was to compare the new Actigraph (GT1M) with the widely used Model 7164. Seven days of free-living physical activity were measured simultaneously using both the Model 7164 and GT1M in 30 Indian adolescents (mean age 15.8 years, s = 0.6). The GT1M was on average 9% lower per epoch than model 7164, thus a correction factor of 0.91 is suggested for comparison between the two monitors. The differences between monitors increased in magnitude with intensity of activity (P < 0.001) but remained randomly distributed (r = 0.01, P = 0.96). No significant difference was observed between monitors for time spent in moderate (P = 0.31) and vigorous (P = 0.34) physical activity when using the same epoch length. The Model 7164 classified less time as sedentary (P < 0.001) and more time as light-intensity activity (P < 0.001) than the GT1M. In conclusion, data from the GT1M can be compared with historical data using average counts per minute with a correction factor, and the two models might be comparable for assessing time spent in moderate to vigorous physical activity in children when using the same epoch length.     

The Future of Defunct Religious Buildings: Dutch Approaches to Their Adaptive Re-use

Across the Western world, membership in the established organized churches is on the decline with a concomitant reduction in the need for churches and church halls. As redundant and unused churches are the focus of vandalism and decay, owners and heritage managers are looking for options to adaptively re-use such buildings. This article reviews the literature on the re-use of churches in the Netherlands, which has long history of innovatively addressing the problems. The options available range from re-use for religious purposes by other denominations or faiths, to community use (multi-purpose, sport, music etc.), and private use, which can be either commercial or residential. The attitudes of the community and the original property owners play a major part in successful adaptive re-use. Because of its long history, the Dutch experience in adaptive re-use of religious buildings has much to offer heritage managers in other countries faced with this emergent management issue.     

Shoe drop reduction influences the lower limb biomechanics of children tennis players during an open stance forehand: A longitudinal study

Compared to traditional tennis shoes, using 0-drop shoes was shown to induce an immediate switch from rear- to forefoot strike pattern to perform an open stance tennis forehand for 30% of children tennis players. The purpose of the study was to examine the long-term effects of a gradual reduction in the shoe drop on the biomechanics of children tennis players performing open stance forehands. Thirty children tennis players participated in 2 laboratory biomechanical test sessions (intermediate: +4 months and final: +8 months) after an inclusion visit where they were randomly assigned to control (CON) or experimental (EXP) group. CON received 12-mm-drop shoes twice, whereas EXP received 8?mm then 4-mm-drop shoes. Strike index indicated that all CON were rearfoot strikers in intermediate and final test sessions. All EXP were rearfoot strikers in intermediate test session, but half the group switched towards a forefoot strike pattern in final test session. This switch resulted in a decreased loading rate of the ground reaction force (?73%, p?=?.005) but increased peak ankle plantarflexors moment (+47%, p?=?.050) and peak ankle power absorption (+107%, p?=?.005) for these participants compared with CON. Biomechanical changes associated with the long-term use of partial minimalist shoes suggest a reduction in heel compressive forces but an increase in Achilles tendon tensile forces.