Jason Lezak again and again - linear mixed modelling analysis of change–over times in relay swimming races

The aim of this study was to examine the importance of the change-over time in swimming relay races. Top-class international 4 x 100 m freestyle races were analysed across a 10-year period including three Olympic Games and five European and World Championships. A total of 220 swimmers (116 female, 104 male) were included in this study with an average participation of 1.7 ± 1.2 races. To consider such repeated measurements and other factors (e.g., ranking in the relay race, position in the relay team) linear mixed models for longitudinal data were used for the statistical evaluation. Our results showed significantly longer change-over times for male medallists (0.23 ± 0.08 s) than non-medallists (0.20 ± 0.09 s) which reflects a very likely effect (94.2%). Furthermore, there were significant differences in change-over times between female and male swimmers depending on the current race positions. In total, the influence of change-over time on the final performance in 4 x 100-m freestyle relay appears to be overrated in previous studies.     

Learning relay start strategies in swimming: What feedback is best?

In the past, studies and book recommendations on relay starts in swimming have been predominantly focused on the change-over time (COT) as a performance criterion. Aside from the circular backswing start with parallel foot placement, few studies have analysed differences in the take-off movement including step approaches as well. Although trends could be identified, the results remained still somewhat inconclusive. In contrast, no study has examined as has examined whether a reduction of COT in between wall contact of the income swimmer and the take-off of the outgoing swimmer is an optimal relay start strategy, as advocated by various swimming experts. Therefore, the purpose of this study was to compare two different relay start strategies: offensive strategy minimizing COT and conservative strategy to maximize horizontal peak force (HPF). In this regard, a learning intervention with 24 elite-level swimmers (12 females, 12 male) was conducted to compare both strategies regarding relay start time, HPF and COT. Subjects were randomly assigned to two feedback groups: COT versus HPF at take-off. The results of this study showed a clear advantage for HPF feedback for relay start performance measured by wall contact of the incoming swimmer and head passage at 7.5?m of the outgoing swimmer. In addition, similar reductions in COTs were found in both training groups. In conclusion, swimmers should focus on force production rather than minimizing COT. For the latter, deteriorating consequences for force production must be considered.     

Inclusion in Israel: coping resources and job satisfaction as explanatory factors of stress in two cultural groups

The aim of this study was to explore the differences between the two cultural groups of Jewish and Arab teachers on several variables and to analyse their link to stress. Specifically, I examined sense of coherence (SOC), sense of school community and job satisfaction among regular Jewish and Arab teachers in regular schools and classes who have special education students in their classes. Furthermore, I investigated how the different coping resources – SOC and sense of school community – explain the stress reactions of state anxiety and state anger directly and indirectly via job satisfaction and also the direct prediction of stress by job satisfaction. Data were gathered from 634 Jewish and Arab teachers (80% Jews) who completed self‐report questionnaires that measured SOC, sense of community, employee satisfaction inventory, state anxiety and state anger. Differences in SOC and sense of school community were found between the two groups such that Jews reported stronger SOC, and Arabs reported stronger sense of school community. Further differences were revealed in the links of the different coping resources to stress reactions. The results are discussed against the backdrop of cultural background and the salutogenic model.     

Policy learning in Swiss research policy—the case of the National Centres of Competence in Research

The article treats the problem of “rationality” in learning processes in research policies. The underlying hypothesis is that there are contemporary efforts in research policy-making, which, against views in organisational sociology like “bounded rationality” or “garbage-can”, endeavour to “rationalise” the process of decision-making in research policies. This hypothesis is worked out by taking one example, the setting-up of the “National Centres of Competence in Research” (NCCR) in Switzerland and analyse the processes that have contributed to the acceptance of this funding measure. Our finding is that Switzerland has introduced some “rationalising devices” but that these devices are still insufficiently institutionalised and can be further elaborated. In addition, it is made clear that goal-oriented problem-solving and interests are closely intertwined and cannot be dissociated from another. This may have distorting effects on the rationality of the learning process. It is, nevertheless, a necessary condition in order to learn at all.     

Local links,local knowledge: Choosing care settings and schools

This article draws on data from two recently completed Economic and Social Research Council funded projects in order to examine class differences and similarities in choice of school and choice of childcare. The authors argue that there is every reason to believe that in many circumstances, within its particular mechanisms and practices, choice produces specific and pervasive forms of inequity. The processes by which working‐class parents in one study chose care settings and schools could be seen as less skilled, less informed, less careful than the decision making of many of the middle‐class respondents. However, this is not an argument that the authors advance, noting instead that the practices and meanings of choice are subject to significant social, cultural and economic variations in terms of who gets to choose, who gets their choices, and what, how and why people choose when they are able to. The authors argue that there are alternative sets of priorities in play for the working‐class respondents, involving attachments to the communal and the local.     

Between the estate and the state: struggling to be a ‘good’ mother

The paper draws on an ESRC‐funded study of 70 families in two London locations. It focuses on a set of contemporary and contradictory political discourses that work on and through the lives of working‐class mothers and thereby create tensions and impossibilities within their lives. We illustrate the ways in which these women are positioned by and within these discourses in ways that leave them vulnerable to political and media criticisms.     

The acute effects of bodyweight suspension exercise on muscle activation and muscular fatigue

This investigation examined effects of two exercise modes (barbell, BB; bodyweight suspension, BWS) on muscle activation, resistance load, and fatigue. During session one, nine resistance-trained males completed an elbow flexion one-repetition maximum (1RM). During sessions two and three, subjects completed standing biceps curls to fatigue at 70% 1RM utilizing a randomized exercise mode. Surface electromyography (sEMG) recorded muscle activation of the biceps brachii, triceps brachii, anterior deltoid, posterior deltoid, rectus abdominis, and erector spinae. BWS resistance load was measured using a force transducer. Standing maximal voluntary isometric contractions of the elbow flexors recorded at 90° were used to determine the isometric force decrement and rate of fatigue (ROF) during exercise. sEMG and resistance load data were divided into 25% contraction duration bins throughout the concentric phase. BWS resulted in a 67.7?±?7.4% decline in resistance load throughout the concentric phase (p?≤?0.05). As a result, BB elicited higher mean resistance loads (31.4?±?4.0?kg) and biceps brachii sEMG (84.7?±?27.8% maximal voluntary isometric contractions, MVIC) compared with BWS (20.4?±?3.4?kg, 63.4?±?21.6% MVIC). No difference in rectus abdominis or erector spinae sEMG was detected between exercise modes. Isometric force decrement was greater during BWS (?21.7?±?7.0?kg) compared with BB (?14.9?±?4.7?kg); however, BB (?3.0?±?0.8?kg/set) resulted in a steeper decline in ROF compared with BWS (?1.7?±?0.6?kg/set). The variable resistance loading and greater isometric force decrement observed suggest that select BWS exercises may resemble variable resistance exercise more than previously considered.     

Classroom wall charts and Biblical history: a study of educational technology in elementary schools in late nineteenth- and early twentieth-century Sweden

This article considers the emergence of classroom wall charts as a teaching technology in Swedish elementary schools in the late nineteenth and early twentieth centuries, using Biblical history teaching as an example. There has been some work done internationally on wall charts as an instructional technology, but few studies have looked at their use in Sweden. With a theoretical approach informed by Martin Lawn’s understanding of teaching technologies, this article shows that wall charts became both an important teaching object and a means of introducing new pedagogical ideas. A study of the official school inspectors’ reports shows that wall charts had spread to most local schools by the end of the nineteenth century, while an analysis of Biblical history textbooks and teaching guidelines shows that visual aids were increasingly integrated into the school curriculum. The wall charts themselves were initially imported, mainly from Germany, but by the end of the nineteenth century they were being produced in Sweden for the domestic market, in keeping with the National Romantic ideals of the day as well as with the new awareness of the importance of adapting images to use in classroom teaching.