The effect of prolonged cycling on pedal forces     

Sanderson DJ  Black A 《Journal of sports sciences》2003,21(3):191-199

The aim of this study was to determine whether cyclists modify the pattern of force application to become more effective during a prolonged ride to exhaustion. Twelve competitive male cyclists completed a steady-rate exercise ride to exhaustion at 80% of their maximum power output at 90 rev x min(-1) on a cycle ergometer. Pedal force, pedal and crank angle data were collected from an instrumented bicycle for three pedalling cycles at the end of the first and final minutes of the exercise test with simultaneous video recording of the lower limbs. Kinematic and force data were combined to compute hip, knee and ankle joint moments. There were changes in the pattern of force application, joint kinematics and joint moments of force. Comparison of the first minute and the final minute ride revealed significantly increased peak effective force (340 +/- 65.0 and 377 +/- 74.8 N for the first and final minute, respectively; F1,11 = 7.44, P = 0.02), increased positive (28.4 +/- 4.5 and 30.5 +/- 4.8 N x s for the first and final minute, respectively; F1,11 = 7.80, P = 0.02) and negative angular impulses (-1.5 +/- 1.6 and -2.4 +/- 1.5 N x s for the first and final minute, respectively; F1,11 = 4.50, P = 0.06). Contrary to our initial assumptions, it would appear that riders became less effective during the recovery phase, which increased the demand for forces during the propulsive phase. Training the pattern of force application to improve effectiveness may be a useful strategy to prolong an endurance ride.  相似文献   

The influence of cadence and power output on force application and in-shoe pressure distribution during cycling by competitive and recreational cyclists     

Sanderson DJ  Hennig EM  Black AH 《Journal of sports sciences》2000,18(3):173-181

The aim of this study was to determine the response of cyclists to manipulations of cadence and power output in terms of force application and plantar pressure distribution. Two groups of cyclists, 17 recreational and 12 competitive, rode at three nominal cadences (60, 80, 100 rev x min(-1)) and four power outputs (100, 200, 300, 400 W) while simultaneous force and in-shoe pressure data were collected. Two piezoelectric triaxial force transducers mounted in the right pedal measured components of the pedal force and orientation, and a discrete transducer system with 12 transducers recorded the in-shoe pressures. Force application was characterized by calculating peak resultant and peak effective pedal forces and positive and negative impulses. In-shoe pressures were analysed as peak pressures and as the percent relative load. The force data showed no significant group effect but there was a cadence and power main effect. The impulse data showed a significant three-way interaction. Increased cadence resulted in a decreased positive impulse, while increased power output resulted in an increased impulse. The competitive group produced less positive impulse but the difference became less at higher cadences. Few between-group differences were found in pressure, notable only in the pressure under the first metatarsal region. This showed a consistent pattern of in-shoe pressure distribution, where the primary loading structures were the first metatarsal and hallux. There was no indication that pressure at specific sites influenced the pedal force application. The absence of group differences indicated that pressure distribution was not the result of training, but reflected the intrinsic relationship between the foot, the shoe and the pedal.  相似文献   

Adrian Peterson and the “Wussification of America”: Football and Myths of Masculinity     

Justin Gus Foote  Michael L. Butterworth  Jimmy Sanderson 《Communication quarterly》2017,65(3):268-284

Twitter has become a unique site for making sense of public discussions about authority and morality in the United States. This article addresses these discussions by analyzing the elements of conservative discourse that claim the health of the nation is in decline because of a diminished emphasis on masculine leadership. There is a long tradition of conservative politicians in the United States warning against “soft” or “weak” figures of authority. Such conversations take place within a range of contexts, including the sport of football. As a means to engage hegemonic masculine authority from a critical perspective, this article investigates Twitter users’ various reactions to Adrian Peterson’s suspension due to his disciplining his child with a “switch.”  相似文献   

Tracing spectres of whiteness: discourse and the construction of teaching subjects in urban Aboriginal education     

Brooke Madden 《Discourse: Studies in the Cultural Politics of Education》2017,38(5):642-658

The author traces how discourse functions in the context of a school-based, urban Aboriginal education initiative, with a focus on the construction and organization of teaching subjects. Critical discourse analysis that traces spectres reveals some of the ways that whiteness and Eurocentrism create the possibilities for, and the conditions in which teachers take up, the positions: victim of racism, arbiter of authenticity, and rescuer. Consideration of the multiple, complex, and shifting positions teachers occupy within whiteness in general, and in colonial systems of education in particular, offers unique possibilities when untangling and reconfiguring teachers' constructions of Aboriginality/Indigeneity and responses to Aboriginal/Indigenous education. This theory building also contributes to the larger field of curriculum studies by demonstrating how consideration of ‘unheroic tales’ can aid in theorizing teacher identity and difference, both within and beyond the markers Indigenous/non-Indigenous.  相似文献   

Integrating evidence-based reading practices into middle-school content instruction: exploring a facet of sustainability     

Brooke A. Moore  Alison G. Boardman  Cristin Jensen Lasser  Kimberly M. Schmidt  Clara E. Smith  Vanessa S. Schwarz 《Teacher Development》2019,23(3):287-306

Reading comprehension models are being implemented in content-area settings to boost reading achievement. Yet, little research explores how such models are incorporated into teachers’ daily instructional practice. The authors used extended observations and interviews to examine the integration of Collaborative Strategic Reading (CSR), an evidence-based reading comprehension model, into the instructional practices of 15 middle school science, social studies, and language arts teachers. Findings indicated that high-integration teachers embedded CSR lessons into their curriculum and reinforced CSR strategy use throughout the week. These teachers also felt supported in their efforts by colleagues and school administrators. There is much to be learned from the ways in which teachers engage in the art of integrating new methods into their teaching.  相似文献   

Exploration of a Blended Learning Approach to Reading Instruction for Low SES Students in Early Elementary Grades     

Rachel Schechter  Paul Macaruso  Elizabeth Brooke 《学校用计算机》2015,32(3-4):183-200

This study investigated the potential benefits of a blended learning approach on the reading skills of low socioeconomic status students in Grades 1 and 2. Treatment students received English language arts instruction that was both teacher-led and technology-based. Comparisons were made with control students who received the same English language arts instruction without the blended learning component. Results showed significantly greater pretest/posttest gains on a standardized reading assessment for the treatment students compared to the control students. The greatest discrepancy occurred in reading comprehension. A sub-analysis of low-performing English language learner students in the treatment group revealed the largest reading gains. At posttest, these students performed at the level of non-English language learner students in the control group. Results indicated a blended learning approach can be effective in enhancing the reading skills of low socioeconomic students.  相似文献   

Meeting in the circle: examining identity,attitudes, and pedagogy in the context of an early childhood teacher education program in the United States     

Simone DeVore  Robin Fox  Lucy Heimer  Brooke Winchell 《Early Years: An International Journal of Research and Development》2015,35(4):394-410

As a team of teacher educators at a university in the United States, we engage in participatory action research to reflect on how reflective tools which we design engage teacher candidates (TCs) in their reflecting on teaching. In this paper, we describe how we invite TCs to write in-class reflections, respond to self-assessment probes, and practice problem-solving processes. We critically analyze our approaches and identify further intentional approaches to promote university students’ understandings of (1) links between the self and working with children and families and (2) connections between attitudes and pedagogy towards social justice and inclusion. We conclude that we must continue to explore how the teaching practices we use affect students’ understandings of social justice in education. Doing so demands our focus on examining attitudes through self-reflection among and between faculty and university students so that identity, relationships, attitudes, inclusion, and social justice are prioritized as pillars of curriculum in early childhood education at all levels of schooling.  相似文献   

Exploring women faculty's experiences and perceptions in higher education: the effects of feminism?     

Brooke Midkiff 《Gender and education》2015,27(4):376-392

This study analyses women faculty's discourse about feminism, themselves, and their professional experiences as scholars in the North American university context. This case study pushes at the boundaries of what we believe we know about ‘the gender question' in the academy, opening a discursive space for scholars to examine university policies and practices. Poststructuralist emphasis on the complexity and changing nature of power relations offer a framework that makes sense of the ways in which women are simultaneously affected by power relations and engage in power relations. I use feminist poststructuralist discourse analysis to analyse women's talk about their experiences in order to carve a path for moving beyond the deconstruction of discourse in order to unpack how it marginalises and silences women, even within and to themselves.  相似文献   

Research engagement of health sciences librarians: a survey of research-related activities and attitudes     

Susan Lessick  Carol Perryman  Brooke L. Billman  Kristine M. Alpi  Sandra L. De Groote  Ted D. Babin  Jr. 《Journal of the Medical Library Association》2016,104(2):166-173

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Perfectionism and depressive symptoms in early adolescence     

Kenneth G. Rice  Brooke A. Leever  Chad A. Noggle  Daniel K. Lapsley 《Psychology in the schools》2007,44(2):139-156

The Adaptive/Maladaptive Perfectionism Scale (AMPS; K.G. Rice & K.J. Preusser, 2002) was developed on samples of 9‐ to 11‐year‐old children. A primary purpose of the current research was to examine whether the AMPS could be useful in studies of adolescents, and in particular, studies of adolescent depression. This study of 145 early adolescents revealed (1) a somewhat different AMPS factor structure than has been evident in studies of younger children; (2) no significant mean differences between boys and girls on perfectionism, although girls were significantly more depressed than boys; (3) a pattern of perfectionism‐depression correlations that differed somewhat between boys and girls; and (4) several interactions of different dimensions of perfectionism in accounting for depression. Results are discussed by addressing differences between children and adolescents in school cultures, physical and psychological changes from childhood to adolescence, and the importance of considering the positive as well as the negative aspects of perfectionism among school‐age children. © 2007 Wiley Periodicals, Inc. Psychol Schs 44: 139–156, 2007.  相似文献