Effect of loading on peak power of the bar,body, and system during power cleans,squats, and jump squats

Abstract

Nine males (age 24.7 ± 2.1 years, height 175.3 ± 5.5 cm, body mass 80.8 ± 7.2 kg, power clean 1-RM 97.1 ± 6.36 kg, squat 1-RM = 138.3 ± 20.9 kg) participated in this study. On day 1, the participants performed a one-repetition maximum (1-RM) in the power clean and the squat. On days 2, 3, and 4, participants performed the power clean, squat or jump squat. Loading for the power clean ranged from 30% to 90% of the participant's power clean 1-RM and loading for the squat and jump squat ranged from 0% to 90% of the participant's squat 1-RM, all at 10% increments. Peak force, velocity, and power were calculated for the bar, body, and system (bar + body) for all power clean, squat, and jump squat trials. Results indicate that peak power for the bar, body, and system is differentially affected by load and movement pattern. When using the power clean, squat or jump squat for training, the optimal load in each exercise may vary. Throwing athletes or weightlifters may be most concerned with bar power, but jumpers or sprinters may be more concerned with body or system power. Thus, the exercise type and load vary according to the desired stimulus.     

WHAT GOOD IS GRATITUDE IN YOUTH AND SCHOOLS? A SYSTEMATIC REVIEW AND META‐ANALYSIS OF CORRELATES AND INTERVENTION OUTCOMES

The development of gratitude in youth has received increasing attention during the past several years, and gratitude‐based interventions have often been recommended for use in schools. Yet, the empirical status of the correlates of gratitude and the effects of gratitude‐based interventions on youths’ outcomes remains unclear. The present study addressed this ambiguity by systematically reviewing and meta‐analyzing original empirical journal articles investigating gratitude in youth through September 2014 (N = 20). Findings from the meta‐analysis of correlates indicate small‐to‐moderate convergent and discriminant evidence for gratitude as a subjective well‐being indicator in youth, yet other results indicate that gratitude measures have relatively poor test–retest reliability and/or predictive validity and that they have questionable concurrent validity with other gratitude measures. Moreover, findings from the meta‐analysis of intervention outcomes indicate that gratitude‐based interventions are, as a whole, generally ineffective and that much more intervention research is warranted. Implications of these findings for theory, future research, and the practice of school psychology are discussed.     

Using the Ecosystemic Approach to Change Chronic Problem Behaviour in Primary Schools

This paper describes a small‐scale study of what the authors describe as the ecosystemic approach to changing chronic problem behaviour. The study was undertaken with a group of twelve Leicestershire primary teachers. The technique is briefly described and then teachers' responses to it and its effectiveness are discussed. Four case study examples are presented and finally its potential is considered. Although in this case the work was undertaken with primary teachers, this is an approach which could also be useful at secondary level.     

Reading nonfiction text on an iPad in a secondary classroom

The intent of this research was to investigate the experiences of eighth grade readers as they read nonfiction text on an iPad for academic purposes. We investigated reading strategies that students use to support their reading as well as what role iPad features played in the reading process. New literacies, metacognition and transactional theories informed the framework. Multiple data sources were used to triangulate findings and included (a) retrospective think alouds, (b) student iPad survey, (c) pre and post study student interviews, (d) Metacognitive Awareness of Reading Strategies Inventory and (e) student observations. Data for the collective case study participants focused on the identification of proficient readers who displayed confidence, competency, and control over text. Themes identified in the collective case studies included (a) reading comprehension strategies, (b) nonfiction features and (c) iPad features to support their reading of nonfiction on the iPad.     

The Rise of the Creative Underclass

In this article, Tyler Denmead draws upon critical race theory to argue that the creative city discourse reproduces racial injustice for youth. In particular, the creative city invests in the property rights and profitability of whiteness by inscribing creative superiority on the bodies of young people who are more likely to be privileged by virtue of their race and class. Through evidence collected by both autoethnographic and ethnographic methods, Denmead discusses how his history as an arts educator has been entangled in the manifestation of this racist reconfiguration of urban space in one particular American city, Providence, Rhode Island. He discovered that the racial dynamics of the creative city discourse have productive power over how young people construct their identities and make life choices in this city and, further, that those dynamics operate in and through artist partnerships between those positioned as creatives and those positioned as troubled youth. As a result, Denmead argues that white arts educators, in particular, must disinvest themselves from notions of creativity that enhance the profitability and power of whiteness. This move requires advocating ceding land and resources that have been acquired through the creative city discourse and committing to reframing culture‐led urban renewal in terms of the economic and creative flourishing of communities of color.