Kinematic differences between front crawl sprint and distance swimmers at a distance pace

Abstract

The purpose of the study was to determine whether there are differences in kinematics between sprint and distance front crawl specialists when swimming at a distance pace using a six beat kick. Seven sprint and eight distance male specialists performed one maximum 400 m swim through a 6.75 m³ calibrated space recorded by six gen-locked cameras. The following variables were calculated: average swim velocity, stroke length, stroke frequency, upper limb and foot displacement, elbow angle, the shoulder and hip roll angle, duration of the stroke phases and time corresponding to particular events within the stroke cycle relative to hand entry. Differences between the groups were assessed by an independent t-test and effect size (d) calculations for each variable. The groups only differed significantly with respect to the average swim velocity, with the distance swimmers maintaining a greater velocity throughout the 400 m. However, effect sizes were moderate for elbow angle range during the pull phase (d = 0.78) and the total hip roll magnitude (d = 0.76). There was little evidence to suggest that sprint and distance swimmers using a six beat kick pattern differ in technique when swimming at a distance pace and therefore coaches should not encourage the development of different techniques between these groups.     

Blogging with pre-service teachers as action research: when data deserve a second glance

The implementation of digital pedagogies (i.e. blogging) is one way to mediate large classroom discussions in culturally relevant ways. This 2.5-year longitudinal mixed-method action research study reflects on the ways blogging can further promote culturally relevant discussions explored in face-to-face classes. Findings include pre-service teachers’ use of blogs in: interrogating issues as a means of developing cultural competence; recognizing their own trepidation and lack of self-knowledge related to topics of diversity; and exploring the disconnect between their current knowledge and future practice. Additionally, this study explores ways in which the authors could have further assisted students in challenging their beliefs and strengthening cultural competencies through blog responses.     

An alternate path to stoichiometric problem solving

Stoichiometric problem solving has always been a stumbling block for many students in introductory chemistry courses. Research has shown that it is quite common for students to rely on algorithms when doing stoichiometric calculations. In previous studies, students were confronted with simple stoichiometric problems that involved comparing molar masses with simple ratios to one another. It turned out that students very successfully used their own problem-solving strategies. It is typical of these strategies that students describe relations in their own words rather than applying mathematical calculations. In this paper, an alternate path to teaching introductory stoichiometry-based on the results of research-will be discussed. The recommendation given is to use problems of the kind mentioned above which can easily be solved by quick mental calculation.