Development of a grinding-specific performance test set-up

Abstract

The aim of this study was to develop a performance test set-up for America's Cup grinders. The test set-up had to mimic the on-boat grinding activity and be capable of collecting data for analysis and evaluation of grinding performance. This study included a literature-based analysis of grinding demands and a test protocol developed to accommodate the necessary physiological loads. This study resulted in a test protocol consisting of 10 intervals of 20 revolutions each interspersed with active resting periods of 50 s. The 20 revolutions are a combination of both forward and backward grinding and an exponentially rising resistance. A custom-made grinding ergometer was developed with computer-controlled resistance and capable of collecting data during the test. The data collected can be used to find measures of grinding performance such as peak power, time to complete and the decline in repeated grinding performance.     

‘The life of crime does not pay; stop and think!’: the process of co-constructing a prototype pedagogical model of sport for working with youth from socially vulnerable backgrounds

Purpose: This study discusses the process of co-constructing a prototype pedagogical model for working with youth from socially vulnerable backgrounds.

Participants and settings: This six-month activist research project was conducted in a soccer program in a socially vulnerable area of Brazil in 2013. The study included 17 youths, 4 coaches, a pedagogic coordinator and a social worker. An expert in student-centered pedagogy and inquiry-based activism assisted as a debriefer helping in the progressive data analysis and the planning of the work sessions.

Data collection/analysis: Multiple sources of data were collected, including 38 field journal/observation and audio records of: 18 youth work sessions, 16 coaches’ work sessions, 3 combined coaches and youth work sessions, and 37 meetings between the researcher and the expert.

Findings: The process of co-construction of this prototype pedagogical model was divided into three phases. The first phase involved the youth and coaches identifying barriers to sport opportunities in their community. In the second phase, the youth, coaches and researchers imagined alternative possibilities to the barriers identified. In the final phase, we worked collaboratively to create realistic opportunities for the youth to begin to negotiate some of the barriers they identified. In this phase, the coaches and youth designed an action plan to implement (involving a Leadership Program) aimed at addressing the youths’ needs in the sport program. Five critical elements of a prototype pedagogical model were co-created through the first two processes and four learning aspirations emerged in the last phase of the project.

Implications: We suggest an activist approach of co-creating a pedagogical model of sport for working with youth from socially vulnerable backgrounds is beneficial. That is, creating opportunities for youth to learn to name, critique and negotiate barriers to their engagement in sport in order to create empowering possibilities.     

Researching up and across in physical education and sport pedagogy: methodological lessons learned from an intergenerational narrative inquiry

Of issue in this paper are the ways in which different forms of narrative may be of value in undertaking research in potentially thorny situations. The project that inspired this paper saw 30 Physical Education and Sport Pedagogy (PESP) Early Career Academics (ECAs) from more than 20 universities across Australasia, North America and Europe, provide narrative accounts of their ongoing academic experiences. From these stories, three letters seeking advice and guidance from leaders in the field were constructed. Following further feedback from the ECAs, the 3 letters were sent to 11 professors in the PESP field with a request to respond, also in letter form. The composite letters and the professorial responses were then the subject of a symposium at an international PESP conference. While the larger project engages with questions of being and becoming an academic in the neoliberal university, this paper is primarily concerned with methodological issues, including our steps and missteps with narrative, inquiry and the field. More specifically, the focus is on narrative as both the method and phenomena of study. As such, we consider issues associated with using dialogue as data, the provocation of participants, as well as both the presentation and representation of data and the relative power of the participants. In doing so, we critically engage with issues of anonymity (or lack thereof), the practice of ‘researching up’ and finally reach the conclusion that the careful approach to data generation, treatment and presentation necessitated by this project, should be a more regular feature of all qualitative inquiry.     

Short-term reliability of inflammatory mediators and response to exercise in the heat

Prospective application of serum cytokines, lipopolysaccharide (LPS), and heat shock proteins (eHSPs) requires reliable measurement of these biomarkers that can signify exercise-induced heat stress in hot conditions. To accomplish this, both short-term (7 day) reliability (at rest, n = 12) and the acute responsiveness of each biomarker to exercise in the heat (pre and post 60-min cycling, 34.5°C and 70% RH, n = 20) were evaluated. Serum was analysed for the concentration of C-reactive protein (CRP), interleukin-6 (IL-6), heat shock protein 72 (eHSP72), immunoglobulin M (IgM) and LPS. Test–retest reliability was determined as the coefficient of variation (CV). Biomarkers with the least short-term within-participant variation were IL-6 (19%, ±20%; CV, ±95% confidence limits (CL)) and LPS (23%, ±13%). Greater variability was observed for IgM, eHSP72 and CRP (CV range 28–38%). IL-6 exhibited the largest increase in response to acute exercise (95%, ±11%, P = < 0.001) and although CRP had a modest CV (12%, ±7%), it increased substantially post-exercise (P = 0.02, ES; 0.78). In contrast, eHSP72 and LPS exhibited trivial changes post-exercise. It appears variation of common inflammatory markers after exercise in the heat is not always discernible from short-term (weekly) variation.     

Short-term heat acclimation prior to a multi-day desert ultra-marathon improves physiological and psychological responses without compromising immune status

Multistage, ultra-endurance events in hot, humid conditions necessitate thermal adaptation, often achieved through short term heat acclimation (STHA), to improve performance by reducing thermoregulatory strain and perceptions of heat stress. This study investigated the physiological, perceptual and immunological responses to STHA prior to the Marathon des Sables. Eight athletes (age 42 ± 4 years and body mass 81.9 ± 15.0 kg) completed 4 days of controlled hyperthermia STHA (60 min·day^?1, 45°C and 30% relative humidity). Pre, during and post sessions, physiological and perceptual measures were recorded. Immunological measures were recorded pre-post sessions 1 and 4. STHA improved thermal comfort (P = 0.02), sensation (P = 0.03) and perceived exertion (P = 0.04). A dissociated relationship between perceptual fatigue and T_re was evident after STHA, with reductions in perceived Physical (P = 0.04) and General (P = 0.04) fatigue. Exercising T_re and HR did not change (P > 0.05) however, sweat rate increased 14% (P = 0.02). No changes were found in white blood cell counts or content (P > 0.05). Four days of STHA facilitates effective perceptual adaptations, without compromising immune status prior to an ultra-endurance race in heat stress. A greater physiological strain is required to confer optimal physiological adaptations.     

Physical Inactivity,Obesity, and Type 2 Diabetes: An Evolutionary Perspective

Physical inactivity (and unhealthy nutrition) has distorted body composition and, in turn, reordered the proportions of myocyte and adipocyte insulin receptors. Insulin acting on adipocyte receptors produces less glucose uptake than does comparable interaction with myocyte receptors. Accordingly, in individuals with disproportionate muscle/fat composition, any given glucose load requires greater-than-normal pancreatic insulin secretion for adequate disposal. This hyperinsulinemia then becomes the leading cause of type 2 diabetes (T2DM) as insulin-sensitive tissues become desensitized. Because T2DM is rooted in potentially reversible lifestyle factors, rather than focusing on the intricacies of glucoregulation at the molecular level and on testing new drugs to control blood sugar, this article calls for a new prevention and treatment paradigm, in which exercise and weight control are essential and for which an inexpensive and acceptably accurate measure of body muscle and fat proportions is needed.     

Validity and Reliability of Three Self-Report Instruments for Assessing Attainment of Physical Activity Guidelines in University Students

The purpose of this study was to compare the validity and reliability of three short physical activity self-report instruments to determine their potential for use with university student populations. The participants (N = 155; 44.5% male; 22.9 ± 5.13 years) wore an accelerometer for 9 consecutive days and completed a single-item measure, the a brief two item measure and the International Physical Activity Questionnaire—Short Form questionnaires on day 1 and 9. Correlations between self-reported and accelerometer derived moderate-to-vigorous physical activity levels were moderate for the International Physical Activity Questionnaire—Short Form, while poor for the single-item measure and the a brief two item measure. The agreement level was high with the International Physical Activity Questionnaire—Short Form (77.4%) and moderate for both the single-item measure (45.2 %) and a brief two item measure (44.5 %). The intraclass correlations between the two administrations were moderate to strong across all measures (0.52–0.70) in 133 participants. The International Physical Activity Questionnaire—Short Form is the most suitable of these three self-report instruments for use with this population due to higher correlations and levels of agreement with accelerometry.     

Sports’ disciplinary legacy and the challenge of ‘coaching differently’

Be empowering. Be athlete-centered. Be autonomy supportive. These are three related topics currently being promoted by sport psychologists and sport pedagogists in an effort to recognize athletes’ unique qualities and developmental differences and make coaching more holistic and coaches more considerate. This has led us to ask, how likely are such initiatives to lead to coaches putting their athletes at the center of the coaching process given that coaches’ practices have largely been formed through relations of power that subordinate and objectify athletes’ bodies through the regular application of a range of disciplinary techniques and instruments [e.g. Barker-Ruchti, N., &; Tinning, R. (2010). Foucault in leotards: Corporeal discipline in women's artistic gymnastics. Sociology of Sport Journal, 27, 229–250; Heikkala, J. (1993). Discipline and excel: Techniques of the self and body and the logic of competing. Sociology of Sport Journal, 10, 397–412; Gearity, B., &; Mills, J. P. (2012). Discipline and punish in the weight room. Sports Coaching Review, 1, 124–134]? In other words, to try to develop athlete-centered coaches capable of coaching in ways that will empower their athletes without also problematizing the discursive formation of coaches’ practices concerns us [Denison, J., &; Mills, J. P. (2014). Planning for distance running: Coaching with Foucault. Sports Coaching Review, 3, 1–16]. Put differently: how can athlete empowerment initiatives be anything more than rhetoric within a disciplinary framework that normalizes maximum coach control? It is this question that we intend to explore in this paper. More specifically, as Foucauldians, we will argue that coaching with greater consideration for athletes’ unique qualities and developmental differences needs to entail coaching in a less disciplinary way and with an awareness and appreciation of the many unseen effects that disciplinary power can have on coaches’ practices and athletes’ bodies.