Effect of cadence selection on peak power and time of power production in elite BMX riders: A laboratory based study

ABSTRACT

The aims of this study were to analyse the optimal cadence for peak power production and time to peak power in bicycle motocross (BMX) riders. Six male elite BMX riders volunteered for the study. Each rider completed 3 maximal sprints at a cadence of 80, 100, 120 and 140 revs · min^?1 on a laboratory Schoberer Rad Messtechnik (SRM) cycle ergometer in isokinetic mode. The riders’ mean values for peak power and time of power production in all 3 tests were recorded. The BMX riders produced peak power (1105 ± 139 W) at 100 revs · min^?1 with lower peak power produced at 80 revs · min^?1 (1060 ± 69 W, (F(2,15) = 3.162; P = .266; η² = 0.960), 120 revs · min^?1 (1077 ± 141 W, (F(2,15) = 4.348; P = .203; η² = 0.970) and 140 revs · min^?1 (1046 ± 175 W, (F(2,15) = 12.350; P = 0.077; η² = 0.989). The shortest time to power production was attained at 120 revs · min^?1 in 2.5 ± 1.07 s. Whilst a cadence of 80 revs · min^?1 (3.5 ± 0.8 s, (F(2,15) = 2.667; P = .284; η² = 0.800) 100 revs · min^?1 (3.00 ± 1.13 s, (F(2,15) = 24.832; P = .039; η² = 0.974) and 140 revs · min^?1 (3.50 ± 0.88 s, (F(2,15) = 44.167; P = .006; η² = 0.967)) all recorded a longer time to peak power production. The results indicate that the optimal cadence for producing peak power output and reducing the time to peak power output are attained at comparatively low cadences for sprint cycling events. These findings could potentially inform strength and conditioning training to maximise dynamic force production and enable coaches to select optimal gear ratios.     

Self‐modeling as a treatment for increasing on‐task behavior

The study investigated the effectiveness of self‐modeling as a treatment to increase on‐task behavior. A multiple baseline design across 3 students was employed to determine the treatment effects. In addition, classroom peers' on‐task behavior was employed as comparison data. The results indicated immediate, substantial, and durable changes in students' on‐task behavior that generalized across academic settings. The 3 students evidenced an increase of on‐task behavior from an average of 33% of the intervals observed at baseline to 86% during treatment. At 6‐ and 8‐week follow‐up, the students' percentages of on‐task behavior was essentially indistinguishable from their classroom peers. Consumer data indicated that the teachers and students were satisfied with the procedure. © 2000 John Wiley & Sons, Inc.     

Estimating the Impact of Instructional Practices on Student Achievement in Science

This study used a hierarchical linear model (HLM) to estimate direct and indirect effects of instructional practices recommended by the National Science Education Standards on individual achievement. Three pedagogical reforms—namely, providing more opportunities for laboratory inquiry, increasing emphasis on critical thinking, and reducing the amount of teacher‐centered instruction—were expected to account for variability in school mean achievement and explain why gender, racial‐ethnic status, and socioeconomic status have more influence on achievement of students in some schools than in others. Results suggest that whereas the instructional policies recommended by the authors of the Standards may be associated with higher achievement overall, they are equally likely to have the unintended consequence of contributing to greater achievement gaps among students with different demographic profiles. Theoretical expectations about the impact of instructional practices on academic excellence and equity require further evaluation. © 1999 John Wiley & Sons, Inc. J Res Sci Teach 36: 1110–1126, 1999     

Ratings of severity of life events by ninth-grade students

Special education, basic, and honors students rated the severity of stress for each of the life events on the Source of Stress Inventory (Chandler, 1981). There was a significant positive relationship between the Chandler rankings and the rankings made by the 60 ninth-grade students. Special education students reported they had experienced more of the events than had honors students, and the special education students reported more intense stress for the experienced events. Life experiences considered more stressful by students when compared to the stress values assigned by the Chandler rankings (teachers and mental health workers) include poor grades in school, loss of job by parent, mother beginning to work, birth of brother or sister, increased arguments with brothers and sisters vision problem requiring glasses.     

Consultation: A team approach to keeping it alive

This article sets out to describe how we have kept the model of consultation alive, and what is still, for us, an evolving process and learning experience. We are not planning here to detail the initial development of the model, but to explore the processes and concepts that we continue to use to ensure a genuine team approach is adopted.     

“Along the road to learn”: Children and adults in the picture books of John Burningham

She has published two children's books and a number of articles on chldren's literature. She is particularly interested in the picture book.     

Evidence‐Based Strategies for Reading Instruction of Older Students with Learning Disabilities

Over a quarter of 8th‐grade students and more than one‐third of 4th graders do not read well enough to understand important concepts and acquire new knowledge from grade‐level text. For students with learning disabilities, the numbers are more troubling. This article describes features of evidence‐based instruction for students who continue to struggle with reading in late elementary, middle, and high school. Recommendations are organized into 5 areas that are critical to the reading improvement of older struggling readers: (1) word study, (2) fluency, (3) vocabulary, (4) comprehension, and (5) motivation. Much of the content in this article reflects our efforts with the Special Education and Reading Strands at the National Center on Instruction, funded by the Office of Special Education Programs and the Office of Elementary and Secondary Education. Two reports, both available at http://www.centeroninstruction.org/ , have particular relevance—Interventions for Adolescent Struggling Readers: A Meta‐Analysis with Implications for Practice and Academic Literacy Instruction for Adolescents: A Guidance Document from the Center on Instruction.     

What elements in a sustainability course contribute to paradigm change and action competence? A study at Lincoln University,New Zealand

A significant shift in the dominant paradigm governing the relationship of humans with nature and society is crucial in order to change the current unsustainable practices. This article describes a pilot-study based on a Masters level sustainability course, which explored what specific content, activities and resources may contribute to promoting paradigm change and action competence among university students. Paradigm change and the development of action competence were assessed by analyzing students’ weekly written reflections on their learning experiences and by comparing pre- and post-course questionnaires. At the end of the course students had enhanced their beliefs regarding socio-economic aspects of sustainability and gained an increase in awareness about local sustainability issues. Also some students showed a reframing of certain assumptions related to the dominant paradigm concerning beliefs about the environment and society at large and an increase in self-confidence about promoting change towards sustainability. The main course elements contributing to these results were the class discussions and a structured debate on green growth; an exercise that asked students to reflect on ‘what does my happiness depend on?’; weekly feedbacks which stimulated reflection on what they had learnt; and guest speakers′ accounts of their experiences of putting sustainability into practice.