The effect of exercise-induced muscle damage on isometric and dynamic knee extensor strength and vertical jump performance     

Christopher Byrne  Roger Eston 《Journal of sports sciences》2013,31(5):417-425

In this study, we assessed the effect of exercise-induced muscle damage on knee extensor muscle strength during isometric, concentric and eccentric actions at 1.57 rad · s -1 and vertical jump performance under conditions of squat jump, countermovement jump and drop jump. The eight participants (5 males, 3 females) were aged 29.5 - 7.1 years (mean - s ). These variables, together with plasma creatine kinase (CK), were measured before, 1 h after and 1, 2, 3, 4 and 7 days after a bout of muscle damaging exercise: 100 barbell squats (10 sets 2 10 repetitions at 70% body mass load). Strength was reduced for 4 days ( P ? 0.05) but no significant differences ( P > 0.05) were apparent in the magnitude or rate of recovery of strength between isometric, concentric and eccentric muscle actions. The overall decline in vertical jump performance was dependent on jump method: squat jump performance was affected to a greater extent than countermovement (91.6 - 1.1% vs 95.2 - 1.3% of pre-exercise values, P ? 0.05) and drop jump (95.2 - 1.4%, P ? 0.05) performance. Creatine kinase was elevated ( P ? 0.05) above baseline 1 h after exercise, peaked on day 1 and remained significantly elevated on days 2 and 3. Strength loss after exercise-induced muscle damage was independent of the muscle action being performed. However, the impairment of muscle function was attenuated when the stretch-shortening cycle was used in vertical jumping performance.  相似文献   

Variants within the COMP and THBS2 genes are not associated with Achilles tendinopathy in a case-control study of South African and Australian populations     

Colleen J. Saunders  Lize Van Der Merwe  Jill Cook  Christopher J. Handley  Malcolm Collins 《Journal of sports sciences》2013,31(1):92-100

Abstract

Cartilage oligomeric matrix protein is a structural protein of the extracellular matrix, while thrombospondin-2 is a matricellular protein involved in cell–matrix interactions. Recent studies have shown that genetic variation is a significant risk factor for Achilles tendinopathy, and the genes encoding cartilage oligomeric matrix protein (COMP) and thrombospondin-2 (THBS2) were identified as good candidate genes for association with Achilles tendinopathy. This study aimed to test the association of sequence variants within these candidate genes with the risk of Achilles tendinopathy in participants from South Africa (SA) and Australia (AUS). Three-hundred and forty (133 SA; 207 AUS) control participants with no history of Achilles tendinopathy and 178 (94 SA; 84 AUS) participants clinically diagnosed with Achilles tendinopathy were genotyped for five single nucleotide polymorphisms within the COMP and THBS2 genes in this case-control study. There was no difference in genotype distributions between control and tendinopathy groups for either the THBS2 variants rs9505888, rs6422747 and rs9283850, or the COMP variants rs730079 and rs28494505 in the SA and AUS populations. As the selection of COMP and THBS2 as candidate genes was hypothesis driven, based on biological function, the possibility that other variants within these genes are associated with Achilles tendinopathy cannot be excluded.  相似文献   

Improving the TAMI for use with athletes     

Christopher R. Madan  Anthony Singhal 《Journal of sports sciences》2013,31(14):1351-1356

Abstract

Athletes have been shown to have greater movement imagery abilities than non-athletes. However, since these differences were observed using questionnaires where participants subjectively judged the vividness of performing imagined movements, it is possible that responses could be biased by other factors such as social desirability. One possible solution is to use an objective test, such as the Test of Ability in Movement Imagery (TAMI; Madan, C. R., & Singhal, A. (2013). Introducing TAMI: An objective test of ability in movement imagery. Journal of Motor Behavior, 45, 153–166.). Unfortunately, young adults perform relatively well on the TAMI, leaving little room for statistical sensitivity in observing higher scores. Here we propose an alternate scoring method for the TAMI that resolves this limitation by weighing items according to their difficulty. We apply this scoring method to existing data and show that this improves the TAMI’s selectivity to measuring ability in movement imagery, rather than related imagery processes. Thus, we have successfully improved the TAMI to be more suited for use with athletic populations.  相似文献   

Application of geographic information technologies to historical landscape reconstruction and military terrain analysis of an American Revolution Battlefield: Preservation potential of historic lands in urbanized settings,Boston, Massachusetts,USA     

Christopher V. Maio  David E. Tenenbaum  Craig J. Brown  Victor T. Mastone  Allen M. Gontz 《Journal of Cultural Heritage》2013,14(4):317-331

Through funding from the National Park Service's American Battlefield Protection Program, geographic information technologies were employed to create a high resolution, spatially accurate representation of the 1775 landscape of Boston's Inner Harbor and to conduct a geospatial and temporal assessment of the location, extent, and preservation potential of an American Revolutionary War battlefield and its associated cultural resources. Geographic information technologies provide the tools and methodologies to accurately create digital representations of historical landscapes. These tools enable the visualization and geospatial analysis of landscapes and significant historical events, greatly enhancing the understanding of temporal and spatial interactions between these events and the physical landscape upon which they occurred. Data sources include historical bibliographic and cartographic records, high resolution orthophotographs, constant value raster grids, and LIDAR data. A military terrain model was created utilizing American Battlefield Protection Program's KOCOA system categories, in order to identify defining features of the battlefield. KOCOA is an acronym which stands for Key terrain, Obstacles, Cover and Concealment, Observation and Fields of Fire, and Avenues of Advancement and Withdrawal. The KOCOA analysis provides an established method for identifying critical defining features of the battle and determining the influence of the landscape on the ephemeral battle events. The base map was created utilizing U.S. Navy Coast Survey maps dating from the mid-19th century. A digital elevation model was created to represent the 1775 topography, utilizing LIDAR data and constant value raster layers. The military terrain analysis provided valuable insights into battlefield events and decisions. Defining features of the battle were also identified and mapped. A detailed Environmental Systems Research Institute's ArcGIS Citation Data Model was used to link landscape and KOCOA features to the historical sources they were derived from. A comprehensive source table was created as part of this effort. The results of this investigation have provided a high resolution dataset of Boston's historical landscape during the time of the American Revolution. The geospatial analysis will aid in the development of long-range management strategies for the Chelsea Creek Battlefield and facilitate the assessment of threats to cultural resources posed by both anthropogenic activities and environmental change. The methodologies and interdisciplinary approach will also be applicable to other investigations seeking to recreate historical landscapes within a geographic information system.  相似文献   

Converting a Face-To-Face Introductory Research Methods Course to an Online Format: Pedagogical Issues and Technological Tools     

Mary Secret  Christopher Jennings Ward  Ananda Newmark 《Journal of Teaching in Social Work》2019,39(4-5):455-476

ABSTRACT

This paper presents a step-by-step conversion of a face-to-face (F2F) entry level social work research methods course to a computer-mediated format. An overview of teaching practices and the important pedagogical foundations associated with this curricular effort are discussed followed by an introduction to the electronic platform utilized in the course. Five new teaching practices that guide the F2F-to-online course conversion of this introductory research methods course are presented with corresponding teaching activities and technological tools. A conversion matrix aligns the teaching practices, classroom activities, and provides references for the identified tools.  相似文献   

Trajectories,institutions, and re-locations: a conversation on Inter-Asia outside Asia     

Christopher Lee  Kuan-Hsing Chen  Sneja Gunew  Michelle O’Brien  Audrey Yue  Rusaba Alam 《Inter-Asia Cultural Studies》2019,20(2):341-355

ABSTRACT

This conversation explores the resonances of the Inter-Asia project outside the geographical boundaries of Asia. The participants, who represent diverse national, institutional, and professional experiences, discuss the following topics: how Asia and the Inter-Asia project has affected their intellectual trajectories; navigating academic institutions and formations; the changing meaning of diaspora and migration and their effects on language and communication; and the relationship between the academy and social movements. Particular attention is paid to reframing Australia and Canada from an Inter-Asia perspective.  相似文献   

An Investigation Into Handedness and Choking Under Pressure in Sport     

Christopher Mesagno  Jacob Garvey  Stephanie J. Tibbert  Peter Gröpel 《Research quarterly for exercise and sport》2019,90(2):217-226

When athletes fail to perform at an expected level during an important moment, it is implied the athletes have experienced “choking“ (sudden decline in performance) under pressure.”. Researchers have reported that persistent left-hemispheric activation patterns occur when an athlete experiences considerable performance deteriorations under pressure. Researchers have also observed differences in brain activation patterns between left- and right-handed people on a variety of physical and cognitive tests, with the left-hemispheric activation more pronounced in right-handed participants. Purpose: The purpose of this study was to investigate whether athletes’ handedness may be linked to choking susceptibility (i.e., likelihood to experience performance decline under pressure). Method: Twenty right-handed and 13 left-handed experienced Australian football players completed 15 shot attempts, in both a low-pressure and a high-pressure condition. Both groups displayed equal state anxiety increases due to the pressure manipulation, indicating similar increases in anxiety in both handedness groups. Results: Differences were indicated in performance between the left- and right-handed groups during the high-pressure condition, with the left-handed group maintaining, and the right-handed participants declining, performance. Conclusion: Future electroencephalogram (EEG) research investigating this link may clarify the effect between handedness and choking.  相似文献   

Heat maps: a case for inclusion in secondary statistics instruction     

Christopher Engledowl 《Teaching Statistics》2019,41(2):42-46

Heat maps have become ubiquitous in the media, yet students are rarely exposed to them and their inherent limitations and potential for misleading consumers. This article makes a case for exposing students to them in statistics instruction at the secondary and tertiary level.  相似文献   

Basic values predict doping likelihood     

Christopher Ring  Maria Kavussanu  Bahri Gürpınar 《Journal of sports sciences》2020,38(4):357-365

ABSTRACT

Basic values, defined as trans-situational goals that vary in importance and act as guiding principles in life, have been linked with unethical cognitions, emotions and actions. Their roles in doping, a form of cheating in sport, have yet to established. College athletes reported doping likelihood in hypothetical scenario-based situations and completed measures of basic values, moral disengagement, and anticipated guilt. Correlation analysis showed that doping likelihood was positively associated with self-enhancement values but negatively associated with self-transcendence values and conservation values. Moral disengagement correlated positively with self-enhancement values and negatively with self-transcendence values, whereas guilt correlated positively conservation values and negatively with self-enhancement values and openness to change values. Regression analyses showed that self-enhancement values positively predicted doping likelihood directly, self-transcendence values negatively predicted doping likelihood indirectly via moral disengagement and guilt, and conservation values negatively predicted doping likelihood indirectly via guilt. In line with theory and evidence concerning the relationship between basic value systems and moral thought and action, we found that the values of athletes are directly (self-enhancement) and indirectly (self-transcendence, conservation) linked with likely use of banned performance enhancing substances, an expression of cheating in sport.  相似文献   

Digital Literacies: Social Learning and Classroom Practices Victoria Carrington and Muriel Robinson (Eds.)(2009) London: SAGE Publications Ltd. ISBN: 978‐1‐84787‐038‐4; £20.99; 174 pp.     

Robyn Cox 《Literacy》2012,46(1):56-56

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