• Reduction of myoblast differentiation following multiple population doublings in mouse C2 C12 cells: a model to investigate ageing?

      Sharples, Adam P.; Al-Shanti, Nasser; Lewis, Mark P.; Stewart, Claire E.; University of Bedfordshire (2011-12)
      Ageing skeletal muscle displays declines in size, strength, and functional capacity. Given the acknowledged role that the systemic environment plays in reduced regeneration (Conboy et al. [2005] Nature 433: 760-764), the role of resident satellite cells (termed myoblasts upon activation) is relatively dismissed, where, multiple cellular divisions in-vivo throughout the lifespan could also impact on muscular deterioration. Using a model of multiple population doublings (MPD) in-vitro thus provided a system in which to investigate the direct impact of extensive cell duplications on muscle cell behavior. C(2) C(12) mouse skeletal myoblasts (CON) were used fresh or following 58 population doublings (MPD). As a result of multiple divisions, reduced morphological and biochemical (creatine kinase, CK) differentiation were observed. Furthermore, MPD cells had significantly increased cells in the S and decreased cells in the G1 phases of the cell cycle versus CON, following serum withdrawal. These results suggest continued cycling rather than G1 exit and thus reduced differentiation (myotube atrophy) occurs in MPD muscle cells. These changes were underpinned by significant reductions in transcript expression of: IGF-I and myogenic regulatory factors (myoD and myogenin) together with elevated IGFBP5. Signaling studies showed that decreased differentiation in MPD was associated with decreased phosphorylation of Akt, and with later increased phosphorylation of JNK1/2. Chemical inhibition of JNK1/2 (SP600125) in MPD cells increased IGF-I expression (non-significantly), however, did not enhance differentiation. This study provides a potential model and molecular mechanisms for deterioration in differentiation capacity in skeletal muscle cells as a consequence of multiple population doublings that would potentially contribute to the ageing process.
    • Reduction of total lung capacity in obese men: comparison of total intrathoracic and gas volumes

      Watson, R.A.; Pride, N.B.; Thomas, E. Louise; Fitzpatrick, Julie; Durighel, Giuliana; McCarthy, John; Morin, Stanislas X.; Ind, P.W.; Bell, Jimmy D.; National Heart and Lung Institute; et al. (American Physiological Society, 2010-03-18)
      Restriction of total lung capacity (TLC) is found in some obese subjects, but the mechanism is unclear. Two hypotheses are as follows: 1) increased abdominal volume prevents full descent of the diaphragm; and 2) increased intrathoracic fat reduces space for full lung expansion. We have measured total intrathoracic volume at full inflation using magnetic resonance imaging (MRI) in 14 asymptomatic obese men [mean age 52 yr, body mass index (BMI) 35–45 kg/m2] and 7 control men (mean age 50 yr, BMI 22–27 kg/m2). MRI volumes were compared with gas volumes at TLC. All measurements were made with subjects supine. Obese men had smaller functional residual capacity (FRC) and FRC-to-TLC ratio than control men. There was a 12% predicted difference in mean TLC between obese (84% predicted) and control men (96% predicted). In contrast, differences in total intrathoracic volume (MRI) at full inflation were only 4% predicted TLC (obese 116% predicted TLC, control 120% predicted TLC), because mediastinal volume was larger in obese than in control [heart and major vessels (obese 1.10 liter, control 0.87 liter, P = 0.016) and intrathoracic fat (obese 0.68 liter, control 0.23 liter, P < 0.0001)]. As a consequence of increased mediastinal volume, intrathoracic volume at FRC in obese men was considerably larger than indicated by the gas volume at FRC. The difference in gas volume at TLC between the six obese men with restriction, TLC < 80% predicted (OR), and the eight obese men with TLC > 80% predicted (ON) was 26% predicted TLC. Mediastinal volume was similar in OR (1.84 liter) and ON (1.73 liter), but total intrathoracic volume was 19% predicted TLC smaller in OR than in ON. We conclude that the major factor restricting TLC in some obese men was reduced thoracic expansion at full inflation.
    • Release of VCAM-1 associated endothelial microparticles following simulated SCUBA dives.

      Vince, Rebecca V.; McNaughton, Lars R.; Taylor, Lee; Midgley, Adrian W.; Laden, Gerard; Madden, Leigh A. (Springer, 2009-03)
      Microparticles (MP) are shed into the circulation from endothelium following activation or apoptosis. Vascular cell adhesion molecule-1 (VCAM-1) is expressed on endothelial cells following activation and here we report quantification of VCAM-1 positive microparticles (VCAM + MP) following simulated SCUBA dives, breathing either air or oxygen. VCAM + MP were quantified pre-dive (09:00 and 13:00) and post-dive (+1, +3 and +15 h) on both air and oxygen dives and compared with control samples taken from the same subjects. VCAM + MP followed a similar trend in all experiments, however both dives caused a change in endothelial state, as measured by VCAM + MP. A significant increase in VCAM + MP was observed 1 h post-air dive relative to the control (p = 0.013), which was not observed after the oxygen dive (p = 0.095). Oxidative stress (TBARS) was correlated with VCAM + MP. Data presented highlights the potential of MP as a biological marker of both endothelial state and decompression illness.
    • Representing valued bodies in PE: a visual inquiry with British Asian girls

      Hill, Joanne; Azzarito, Laura (Taylor and Francis, 2012)
      The paper's aims are to explore varying ways British Asian girls visualise and make sense of themselves as active or sporting bodies, and what this means for their (dis)engagement in physical activity. This study draws on a feminist poststructuralist approach concerning the ways in which young people create multiple subject positions through negotiating or rejecting verbal and visual narratives about physical activity and girlhood.
    • The role of acidosis during multiple bouts of high intensity exercise: subsequent effect of recovery in attenuating fatigue

      Chrismas, Bryna C. (University of Wisconsin, 2008)
      The etiology of fatigue following multiple bouts of high-intensity exercise and the subsequent limitations on exercise performance remains a highly contentious and controversial phenomenon. One important factor that could augment performance is the type of recovery. Therefore, the purpose of this study was to examine the effects of active recovery () vs. passive recovery () on blood acidosis during multiple bouts of forearm-wrist-flexion.
    • The role of physical education and other formative experiences of three generations of female football fans

      Pope, Stacey; Kirk, David; University of Bedfordshire (Routledge, 2012-05-15)
      The experiences of female sports fans have been largely marginalised in academic research to date and little research has examined the formative sporting experiences of female spectators. This article draws on 51 semi-structured interviews with three generations of female fans of one (men's) professional football club (Leicester City), to consider the extent to which sports participation at school and elsewhere influences female football fandom, and also explores the influence of the family in channelling young females into or away from sport. We begin by examining the extent to which women had opportunities to experience football at school and how the type of school they attended affected these opportunities. We consider continuities and discontinuities between each generation's experiences by examining the influence of sexist teachers, the ubiquity of what the women viewed as ‘body conscious girls’ and the effects of peer pressure. Finally, we examine the ways in which families obstructed or facilitated young females’ interest in football, and the importance of mainly male role models within and beyond the family. We conclude with some reflections on feminist praxis and its relevance for young people's formative sporting experiences.
    • ‘Seeing the trees not just the wood’: steps and not just journeys in teacher action research

      Casey, Ashley (Taylor and Francis, 2013)
      Employing a number of data-gathering tools (reflective journals, unit diaries, post-cycle reflective analyses, student interviews and observations) this paper examines the residual and emergent effects of cooperative learning on the participants in a second, sequential unit of track and field athletics taught a year after the first intervention. It suggests that learning was both academic and social, and that participants felt the unit built on their prior learning about track and field because it was progressive, motivational and student-centred. The paper concludes by suggesting that, in seeking to understand a teacher’s pedagogical and curricular change process, we need to intersperse research that focuses on the journey towards change with research that explores the individual processes of change.
    • Selenium supplementation and exercise: effect on oxidant stress in overweight adults

      Savory, Louise A.; Kerr, Catherine J.; Whiting, Paul; Finer, Nicholas; McEneny, Jane; Ashton, Tony; University of Bedfordshire (Wiley, 2012-04)
      Both obesity and acute high-intensity exercise increase oxidant stress levels. This study investigates whether selenium (Se) supplementation could be a potential effective therapy to reduce obesity-associated oxidant stress and exercise-induced oxidant stress. Ten normal-weight (NW) (22.80 ± 0.41 kg/m(2)) and ten overweight (OW) healthy subjects (28.00 ± 0.81 kg/m(2)) were assessed during a randomized double-blind Se supplementation study (200 µg sodium selenite/day for 3 weeks) with a 3-week placebo control and inversion of treatment periods. Blood levels of lipid hydroperoxide (LH), superoxide dismutase (SOD), erythrocyte glutathione (GSH), and total antioxidant status (TAS), were measured at rest, pre-, and postexercise (30 min 70% VO(2) max before and after treatment (pretreatment (week 0 and 12) and post-treatment (week 3 or 15)). At rest, compared to placebo, Se supplementation had no significant effect on LH, SOD, GSH, and TAS levels. However, Se supplementation decreased LH levels in the OW group, immediately postexercise (-0.25 ± 0.12 µmol/l, P = 0.05) compared to placebo treatment. Postexercise, with or without Se supplementation, no changes in TAS, SOD, and GSH levels were observed in both the NW and OW group. This study has highlighted a potential benefit of Se in reducing LH levels postexercise in OW individuals. Given that oxidant stress is a predictor of coronary events, it is imperative to better understand oxidant stress-related responses to lifestyle factors (in particular "high-risk" population groups) and potential antioxidant therapy.
    • Situated learning as a theoretical framework for sport education

      Kirk, David; Kinchin, Gary (Sage Publications, 2003-10)
      The article seeks to establish the usefulness of situated learning theory as a means of thinking differently about the alleged abstraction of school learning in a range of subjects including physical education, and the issue of transfer of learning. Following a discussion of Lave and Wenger’s notion of situated learning as legitimate peripheral participation in communities of practice, the article explores the potential of Siedentop’s sport education model as a means of providing young people with educative and authentic experiences of sport as legitimate peripheral participants. It is concluded that sport education may have the potential to provide educative and authentic experiences of sport, but that further detailed empirical investigation is required to establish the conditions in which this potential might be realized.
    • Social positioning and the construction of a youth sports club

      Kirk, David; MacPhail, Ann (Sage Publications, 2003-03)
    • Sport Education as a pedagogical application for ethical development in physical education and youth sport

      Harvey, Stephen; Kirk, David; O'Donovan, Toni M.; University of Bedfordshire (2012-05-15)
      The purpose of this paper is to consider four pedagogical applications within the Sport Education model to examine the ways in which a young person can become a literate sports person and develop ethical behaviour through engagement in physical education and youth sport. Through a systematic review of the Sport Education research literature we present evidence to suggest that although notions such as inclusion, responsibility and ownership, personal and social development and social justice are part of the architecture of this pedagogical model, our findings show that rather than simply being caught, ethical conduct must be taught. Consequently, in the final part of the paper, we present four pedagogical applications within Sport Education that physical education teachers as well as youth sport practitioners and administrators may find useful to promote ethical development: (1) ethical contracts; (2) sports panels; (3) modified games; and (4) awards and rewards.
    • Sport Education, critical pedagogy and learning theory: toward an intrinsic justification for physical education and youth sport

      Kirk, David; Leeds Metropolitan University (Human Kinetics, 2006-05)
      I argue in this paper that sport should be retained as an important part of the educational rationale for physical education. I consider Siedentop's critique of physical education and his alternative in the form of Sport Education. Siedentop's goals for youth sport and physical education and use of the work of Alisdair McIntyre are explored. It is argued that if we work to experience activities that are inherently pleasurable and intrinsically satisfying, then there is a possible future for activities such as sport. I conclude that school physical education is well placed to take up this challenge of sustaining sport as a moral practice and that the pedagogical tools already exist to do this in the form of a critical pedagogy.
    • Sport education: promoting team affiliation through physical education

      MacPhail, Ann; Kirk, David; Kinchin, Gary (Human Kinetics, 2004-04)
      The development of feelings of identity, the sense of belonging to a team, and the growth of social skills are experiences that sport, if properly conducted, is well placed to offer (Siedentop, 1994). Evidence suggests that some characteristics of traditional, multiactivity forms of physical education work against realizing these goals (Locke, 1992). Siedentop's Sport Education (SE) model is one attempt to overcome this shortcoming by recasting units as seasons and maintaining persisting groups as teams throughout the season. Extended units intended to foster team affiliation while promoting affective and social development are common objectives in physical education. We report on a 16-week SE unit that includes over 70 Year-5 students (9- to 10-year-olds) from one UK school. Our findings show that the opportunity to become affiliated with a team was an attractive feature of the pupils' physical education experience and that, under the framework of SE, there was an obvious investment made by the Year-5 Forest Gate students in relation to their sense of identity and involvement as members of a persisting group.
    • Student investment in a research methods course: the influence of achievement goals on motivational patterns

      Hall, Howard K.; Hill, A.P.; Appleton, Paul Richard; Kozub, Stephen A.; University of Bedfordshire (2009)
    • Student learning during a unit of student-designed games

      Casey, Ashley; Hastie, Peter A.; Rovegno, Inez (Taylor and Francis, 2011)
      Aim of the paper was to examine students' learning during their participation in a unit of student-designed games. Conclusions: The student-designed games provided a forum that allowed students to develop a more sophisticated understanding of game structures and game play, but designing games was not easy. However, the findings of this study support the idea that when students design games they discover the impact of the many elements that make up a game.