Research in soccer has traditionally given more weight to players' technical and tactical skills, but few studies have analyzed the motor skills that underpin specific motor actions. The objective of this study was to investigate the style of play of the world's top soccer players, Cristiano Ronaldo and Lionel Messi, and how they use their motor skills in attacking actions that result in a goal. We used and improved the easy-to-use observation instrument (OSMOS-soccer player) with 9 criteria, each one expanded to build 50 categories. Associations between these categories were investigated by T-pattern detection and polar coordinate analysis. T-pattern analysis detects temporal structures of complex behavioral sequences composed of simpler or directly distinguishable events within specified observation periods (time point series). Polar coordinate analysis involves the application of a complex procedure to provide a vector map of interrelated behaviors obtained from prospective and retrospective sequential analysis. The T-patterns showed that for both players the combined criteria were mainly between the different aspects of motor skills, namely the use of lower limbs, contact with the ball using the outside of the foot, locomotion, body orientation with respect to the opponent goal line, and the criteria of technical actions and the right midfield. Polar coordinate analysis detected significant associations between the same criteria included in the T-patterns as well as the criteria of turning the body, numerical equality with no pressure, and relative numerical superiority.

The aim of this study was to analyze the concurrent validity, test–retest reliability, and capacity to detect changes of four different portable devices used to measure a wide range of neuromuscular parameters derived from countermovement jump (CMJ). An accelerometric device (Myotest), a jump mat (Ergojump), an optical device (Optojump), and a smartphone app (MyJump) were simultaneously examined for concurrent validity against gold-standard measures (motion-capture system and a force platform). Twenty-two CMJ-derived variables were collected from 15 healthy male subjects (n = 60 CMJs). Contraction time (CT) and eccentric duration (EccD) measurements obtained from the Myotest were moderately to largely associated with and not different from force platform measurements (r = 0.31 to 0.64, ES = 0.11 to 0.18) and showed moderate test-retest reliability (intraclass correlation coefficient (ICC) = 0.92 to 0.97, coefficient of variation (CV) = 3.8 to 8.0%). Flight time (FT) and jump height (JH) from Ergojump, Optojump, and MyJump showed moderate to strong associations with gold-standard measurements (r = 0.57 to 0.98) and good test–retest reliability (ICC = 0.54 to 0.97, CV = 1.8 to 4.2). However, all portable devices underestimated JH (ES = 1.25 to 2.75). Independent of the instrument used, the analyzed CMJ variables showed good capacity to detect changes (standard error of measurement (SEM) < smallest worthwhile change (SWC)), with the exception of rate of force and rate of power development parameters, which showed marginal capacity (SEM > SWC). The Myotest is preferable to measure temporal parameters during ground contact, whereas Ergojump, Optojump, and MyJump devices may be preferable to measure FT and JH, with the Optojump being the most accurate.

This book analyses protests against the Great Recession in the European periphery. While social movements have long been considered as children of affluent times - or at least of times of opening opportunities - these protests defy such expectations, developing instead in moments of diminishing opportunities in both the economic and the political realms. Can social movement studies still be useful to understanding these movements of troubled times? The authors offer a positive answer to this question, although specify the need to bridge contentious politics with other fields, including political economy. They highlight differences in the social movements’ strength and breadth and attempt to understand them in terms of three sets of dimensions: a) the specific characteristics of the socio-economic crisis and its consequences in terms of mobilization potential; b) the political reactions to it, in what we can define as political opportunities and threats; and c) the social movement cultures and structures that characterize each country. The book discusses these topics through a contextualized analysis of anti-austerity protest in the European periphery

The research about soccer defensive phase shows many limitations regarding the procedures and operational definitions. The aims of this paper are to create an observational instrument based on Dynamic Systems concepts and evidence sufficient content validity to adequately and reliably recode defensive soccer behaviours. For these, a five-stage development process for validity was followed: (1) an initial literature review, instrument development, observation training; (2) adapting an existing systematic observational instrument; (3) pilot study with non-experts; (4) content validity with experts (coaches and researchers) and (5) inter- and intra-observer reliability. Using Aiken’s V coefficient and its cut-off value to determine validity content, consensus was found ( V > 0.67, n = 32, p < 0.05) for all items answered by participants in pilot study and for almost all subjects in the experts’ study ( V > 0.69, n = 12, p < 0.05). Also, Cohen’s Kappa shows inter- and intra-reliability values of 0.87 and 0.90, respectively. The final model, entitled Theoretical Dynamic Model of Soccer Defence, and the observational instrument, named Soccer-Defence, with 14 criteria and category systems, and 106 categories, seems to be suitable for analysing the defensive process in soccer and could be used to find strengths or weaknesses of tactical–technical defensive patterns of play and to help coaches to better prepare their teams.

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