Effects of intensity on muscle-specific voluntary electromechanical delay and relaxation electromechanical delay

The purposes of this study were to examine: 1) the potential muscle-specific differences in voluntary electromechanical delay (EMD) and relaxation electromechanical delay (R-EMD), and 2) the effects of intensity on EMD and R-EMD during step incremental isometric muscle actions from 10 to 100% maximal voluntary isometric contraction (MVIC). EMD and R-EMD measures were calculated from the simultaneous assessments of electromyography, mechanomyography, and force production from the vastus lateralis (VL), vastus medialis (VM), and rectus femoris (RF) during step isometric muscle actions. There were no differences between the VL, VM, and RF for the voluntary EMD_E-M (onsets of the electromyographic to mechanomyographic signals), EMD_M-F (onsets the mechanomyographic to force production), or EMD_E-F (onsets of the electromyographic signal to force production) as well as R-EMD_E-M (cessation of electromyographic to mechanomyographic signal), R-EMD_M-F (cessation of mechanomyographic signal to force cessation), or R-EMD_E-F (cessation of electromyorgraphic signal to force cessation) at any intensity. There were decreases in all EMD and R-EMD measures with increases in intensity. The relative contributions from EMD_E-M and EMD_M-F to EMD_E-F as well as R-EMD_E-M and R-EMD_M-F to R-EMD_E-F remained similar across all intensities. The superficial muscles of the quadriceps femoris shared similar EMD and R-EMD measurements.     

Psychological support for sport coaches: an exploration of practitioner psychologist perspectives

In the present study we add to the literature by exploring the degree to which UK practitioner psychologists perceive themselves able to support sport coaches, and how professional training prepares psychologists for coach work across performance domains. Ten participants comprising seven sport and exercise psychologists with Health Care Professions Council (HCPC) practitioner psychologist status and three trainee psychologists studying towards the British Psychological Society (BPS) qualification in sport and exercise psychology (QSEP) were individually interviewed. All participants reported prior experience of working with coaches across all performance domains. We explored: practitioner’s understanding of the challenges coaches face within their job; practitioner’s experiences of coach work; perspectives about the ways in which practitioners could and should support coaches; and, the degree to which professional training prepares practitioners for coach work. Using recommended procedures of Connelly and Peltzer, content analysis revealed practitioners perceived the challenges faced by coaches are different at grassroots level compared to those working with elite athletes, and that practitioners require skills to provide one-to-one coach support and group-based interventions. All practitioners perceived that training programmes do not adequately equip trainees with skills required for coach work. We discuss the implications for enhancing practitioner training in the UK.     

Coordination variability and skill development in expert triple jumpers

The aim of this study was to examine the influence of skill of expert triple jumpers on the coordination variability of lower extremity intra-limb couplings. In contrast to the traditional motor learning perspective, we hypothesized that as skill and thus performance increases, movement coordination variability will also increase. Three-dimensional kinematic and ground reaction force data were collected during the hop-step transition phase of the triple jump. Relative motion plots and a modified vector coding technique were used to quantify the coordination variability across the trials. The results were consistent with a U-shaped curve, representing coordination variability, as skill increases. The high coordination variability in less skilled athletes is present while the appropriate characteristics defining the movement coordination patterns are acquired. This coordination variability may not be beneficial to performance. As the refinement of these characteristics is achieved, coordination variability decreases, resulting in a more consistent or regulated performance. In the final stages of developing a skilled performance, a functional variability is accessed that brings flexibility to the system allowing it to cope with perturbations. This study highlights the need to address the learning effect when analysing coordination variability from a dynamical systems perspective.     

A person-centered approach to achievement goal orientations in competitive tennis players: Associations with motivation and mental toughness

Background:Research on achievement goal orientations in sport has typically relied on the use of variable-centered approaches that tend to overlook population heterogeneity.In this study,we used a person-centered approach to identify subgroups of competitive tennis players according to unique combinations of achievement goal orientations and tested for subgroup differences in motivation and mental toughness.Methods:A sample of 323 competitive tennis athletes(69.35%male)between 15 and 25 years of age(17.60±2.40 years,mean±SD)completed the 3×2 Achievement Goal Questionnaire for Sport,Sport Motivation Scale Ⅱ,and Mental Toughness Index.Latent profile analysis was used to identify unique combinations of achievement goal orientations.Comparisons between latent subgroups on autonomous motivation,controlled motivation,and mental toughness were performed using analysis of variance.Results:Latent profile analysis supported 3 distinct patterns of achievement goal profiles that were primarily distinguishable based on valence of competence(i.e.,approach vs.avoidance).Analyses of variance indicated that athletes who were classified into subgroups that endorsed approach types of goals(regardless of the types of avoidance goals they endorsed)reported higher levels of autonomous motivation and mental toughness.Conclusion:Results indicated that athletes tend to pursue a number of achievement goals collectively rather than in isolation.Although approach goals are more commonly linked to adaptive psychological functioning and positive outcomes,avoidance goals may also be associated with desirable psychological characteristics if they are pursued in conjunction with approach types of achievement goals.     

Enhancing Student Learning in Food Engineering Using Computational Fluid Dynamics Simulations

Abstract: The current generation of students coming into food science and engineering programs is very visually oriented from their early experiences. To increase their interest in learning, new and visually appealing teaching materials need to be developed. Two diverse groups of students may be identified based on their math skills. Food science students tend to find it difficult to use mathematics as a problem‐solving tool for food engineering problems. Food engineering students, on the other hand, should be challenged to use emerging mathematical tools to develop their problem‐solving skills. Therefore, the approach of this project involved the development of a curriculum to train undergraduate food engineers in the effective use of computational fluid dynamics (CFD) software to solve food engineering problems by engaging them in the creation of food engineering teaching tools. These CFD outputs were then used as innovative teaching tools for the food science students. In this paper, this concept will be illustrated by unsteady‐state heat transfer and fluid flow problems. To evaluate the efficiency of the teaching materials developed, a student focus group was asked to answer the same quiz following a conventional and CFD output aided teaching session. The assessment result showed an improved understanding of the subject after the CFD teaching session. These visual aids were excellent tools to illustrate the validity of the formulas presented in class. In addition, the new visual materials enabled a better understanding of the relationships among different process parameters. In general, this helped the food science students better appreciate the food engineering concepts that govern food processing operations.     

Authentic school partnerships for enabling inclusive education in Hong Kong

Education reform towards a whole school approach to catering for diversity within Hong Kong government schools has seen the initiation of several strategies to support mainstream schools in this transition. One of these approaches is the use of a resource school model. Special and mainstream schools in Hong Kong are being invited to establish themselves as resource support hubs for partner mainstream schools. This paper investigates how this model is being implemented by considering one of each type of resource school. Three broad themes have emerged that relate to the type of support being offered and sought: the school ethos and culture of the partner schools; and management issues. The effectiveness of a resource model is evaluated for its use in Hong Kong.     

Impact of age on haematological markers pre- and post-marathon running

This study investigated whether haematological markers differ between young and masters marathon participants, running at similar performance levels. Nine young (31.89 ± 4.96 years) and eight masters (63.13 ± 4.61 years) runners participated. At five time points (pre-race through 54 h post-race), a complete blood cell count, basic metabolic panel and creatine kinase (CK) isoenzyme panel were assessed. Race performance was standardised using the World Masters Association Age Grading Performance Tables. Total CK levels were elevated for all participants at all time points post-race (P < 0.001). The CK-isoenzyme MB% was elevated across groups at 6, 30 and 54 h post-race (P < 0.01, P < 0.01 and P < 0.05), with masters runners having a higher CK-MB% at 30 and 54 h (P < 0.05, P < 0.05). Total white blood cell and neutrophil counts were elevated through 6 h post-race (P < 0.001), with higher levels found in younger runners (P < 0.001). When considering all blood work, masters runners had a higher number of abnormal values at 6, 30 and 54 h post-race (P < 0.05, P < 0.01 and P < 0.05). In conclusion, masters runners demonstrated sustained CK-MB elevation, which may suggest greater cardiac stress. However, future studies using additional cardiac markers should be completed to confirm these findings. In addition, masters runners showed an increased number of laboratory values outside normal range, indicating the body’s reduced capacity to respond to marathon running.     

‘Muscles for Motherhood’: A Genealogical Analysis of Medicalized Ways of Knowing Female Footballers in New Zealand, 1921 and 1973–1975

ABSTRACT

Michel Foucault argued that females gradually became integrated into the sphere of medical practices through a process which he termed as a ‘hysterization of women’s bodies’ (Foucault, The History of Sexuality, Volume One: An Introduction, New York: Pantheon Books, 1978, 104). In this article, we draw on Foucault to examine how women’s bodies, exercise and motherhood impacted on the historical development of female football in New Zealand within two time periods (1921 and 1973–1975). Employing his genealogical framework, we analyze newspaper reports, historical documents and conducted in-depth interviews to demonstrate how medical/scientific discourses both constrained and enabled the participation of women in football. We conclude that while medical knowledge was used to publicly disqualify the legitimacy of the female footballer in 1921, and hence her abrupt disappearance from the sporting realm, the absence of such medical knowledge in the early 1970s, combined with societal changes associated with second wave feminism, paved the way for the eventual ‘normalization’ of female football in New Zealand.