A systematic review on small-sided games in football players: Acute and chronic adaptations

Small-sided games (SSG) are played on a small pitch, often using modified rules and involving a smaller number of players. This article aimed to critically analyse the literature to determine how small-sided games affect the performance of football players in the short- and long term. Electronic databases were searched for literature dating from January 2000 to July 2018. The methodological quality of the studies was evaluated using the modified Downs and Black Quality Index (cross-sectional studies) and the Physiotherapy Evidence Database (PEDro) scale (intervention studies). Fifty-three studies, 44 cross-sectional and 9 intervention studies, met the inclusionary criteria for review. Most of the cross-sectional studies focused on describing the differences between SSG protocols, whereas 4 studies focused on making a comparison between “interval” and “continuous” SSG training regimes. On the other hand, intervention studies focused on making a comparison between SSG-based protocols and high-intensity intermittent training (HIIT)-based running protocols, in addition to determine the effect of a SSG-based training programme alone. SSG-based football plans (2 to 4 SSG sessions per week) show athletic performance improvements in football players by improving sprint, repeated sprint ability (RSA) and change of direction (COD) along with muscular and physiological adaptation.     

Effectiveness of pedalling retraining in reducing bilateral pedal force asymmetries

ABSTRACT

Previous studies have been limited to describe asymmetries during pedalling and suggest possible repercussion on performance and/or injury risks. However, few studies have presented strategies to mitigate asymmetries. The purpose of this study was to assess the effectiveness of a pedalling retraining intervention to reduce bilateral pedal force asymmetries. Twenty cyclists were assessed and 10 enrolled in a pedalling retraining method receiving visual and verbal feedback of pedal forces. The asymmetry index was computed for comparison of bilateral peak pedal forces and used during retraining (12 trials at 70% of peak power). Significantly larger asymmetry was observed for asymmetrical cyclists at the first three trials (P < 0.01 and ES = 1.39), which was reduced when post-retraining was compared to measures from symmetrical cyclists (P = 0.69 and ES = 0.18). Cyclists with larger asymmetry (>20%) in bilateral pedal forces reduce their asymmetries using sessions of pedalling retraining and achieve asymmetry indices similar to symmetrical cyclists.     

Sitting Still and Reading: Rethinking the Role of Literary Fiction in Civics Education

In this article Annie Schultz argues that engaging with narratives of resistance and empowerment in literary fiction makes for an important addition to the practice of political education. She is interested, in particular, in what can be gained from the thoughtful contemplation modeled by the inner monologues of literary narrators. Many writers of fiction have turned the inner lives of oppressed characters outward in order for readers to glimpse depictions of moral injustices that mirror those of the real world. Using Ralph Ellison's novel Invisible Man as an example of a literary representation of an existential journey to political consciousness, Schultz explores the imaginative implementation of literature in politically engaged pedagogy that, she argues, results in the development of conscious, articulate citizens.     

Genetic and Environmental Influences on Developmental Milestones and Movement: Results From the Gemini Cohort Study

Purpose: Variability in the timing of infant developmental milestones is poorly understood. We used a twin analysis to estimate genetic and environmental influences on motor development and activity levels in infancy. Method: Data were from the Gemini Study, a twin birth cohort of 2,402 families with twins born in the United Kingdom in 2007. Parents reported motor activity level for each of the twins at age 3 months using the Revised Infant Behavior Rating Scale and reported the ages at which they first sat unsupported, crawled, and walked unaided. Results: Activity level at 3 months and ages when first sitting and crawling were about equally influenced by the shared family environment (45%–54%) and genes (45%–48%). Genetic influences dominated for age when children took their first independent steps (84%). Conclusion: Aspects of the shared family environment appear to be important influences on motor activity levels and early milestones, although the timing of walking may have a stronger genetic influence. Further research to identify the specific environmental and genetic factors that promote early activity may be important for longer-term health outcomes.     

Resisting Assimilation: Deliberate Acculturation by the American English Language Learner

Education policy has historically been viewed as having an influential part in crafting the roles of immigrants in American society. However, while policy makers continue to push their own agendas on English language learners (ELLs), ELLs continue to push back to create their own sense of what it means be an American. This article analyzes how formal and informal language policies have historically driven the instruction of ELLs and argues that despite attempts to enculturate and/or assimilate ELLs into American schools through strict English instruction, students employ a variety of cultural resources to act agentically in their acculturation.     

Comparison of the reliability and validity of scores from two concept‐mapping techniques*

This paper reports the results of a study that compared two concept‐mapping techniques, one high‐directed, “fill‐in‐the‐map,” and one low‐directed, “construct‐a‐map‐from‐scratch.” We examined whether: (1) skeleton map scores were sensitive to the sample of nodes or linking lines to be filled in; (2) the two types of skeleton maps were equivalent; and (3) the two mapping techniques provided similar information about students' connected understanding. Results indicated that fill‐in‐the‐map scores were not sensitive to the sample of concepts or linking lines to be filled in. Nevertheless, the fill‐in‐the‐nodes and fill‐in‐the‐lines techniques were not equivalent forms of fill‐in‐the‐map. Finally, high‐directed and low‐directed maps led to different interpretations about students' knowledge structure. Whereas scores obtained under the high‐directed technique indicated that students' performance was close to the maximum possible, the scores obtained with the low‐directed technique revealed that students' knowledge was incomplete compared to a criterion map. We concluded that the construct‐a‐map technique better reflected differences among students' knowledge structure. © 2001 John Wiley & Sons, Inc. J Res Sci Teach 38: 260–278, 2001     

Prediction of abandonment in Spanish fitness centres

Research question: The increase of physical exercise in fitness centres has turned these facilities in important active lifestyle promoters. However, only between 30% and 60% of subscribers still linked to the sports centre after a year. The aim of this study is to design a model to predict the drop out in fitness centres. Research methods: Monthly data corresponding to the actual behaviour of 14,522 members of three sport centres in Spain were recorded over the course of one year. In order to calculate the likelihood of drop out, logistic regressions were used to create predictive models for each centre. Results and findings: It was possible to predict abandonment of users of sport centres from their historical behaviour, although the predictive models obtained for each centre were not completely coincident. The effectiveness of the models was around 70%. Implications: The analysis of users’ behaviour in a fitness centre can allow to avoid the drop out and therefore the abandonment of physical activity. Segmenting the customers based on the likelihood of drop out may be useful for improving the effectiveness of the strategies of loyalty and for optimizing the organization of human and material resources.