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191.
Erica M. Buckeridge Anthony M.J. Bull Alison H. McGregor 《Journal of sports sciences》2016,34(4):369-378
Lumbar-pelvic kinematics change in response to increasing rowing stroke rates, but little is known about the effect of incremental stroke rates on changes in joint kinetics and their implications for injury. The purpose of this study was to quantify the effects of incremental rowing intensities on lower limb and lumbar-pelvic kinetics. Twelve female rowers performed an incremental test on a rowing ergometer. Kinematic data of rowers’ ankle, knee, hip and lumbar-pelvic joints, as well as external forces at the handle, seat and foot-stretchers of the rowing machine were recorded. Inter-segmental moments and forces were calculated using inverse dynamics and were compared across stroke rates using repeated measures ANOVA. Rowers exhibited increases in peak ankle and L5/S1 extensor moments, reductions in peak knee moments and no change in peak hip moments, with respect to stroke rate. Large shear and compressive forces were seen at L5/S1 and increased with stroke rate (P < 0.05). This coincided with increased levels of lumbar-pelvic flexion. High levels of lumbar-pelvic loading at higher stroke rates have implications with respect to injury and indicated that technique was declining, leading to increased lumbar-pelvic flexion. Such changes are not advantageous to performance and can potentially increase the risk of developing injuries. 相似文献
192.
The purpose of the present study was to compare well-peer mentored and non-peer mentored athletes’ perceptions of satisfaction. A total of 444 intercollegiate athletes (272 well-peer mentored and 172 non-peer mentored) from a variety of sport teams participated in the study. Athletes from both well-peer mentored and non-peer mentored groups reported their satisfaction levels using the Athlete Satisfaction Questionnaire. The results of a MANOVA and follow-up post hoc ANOVAs showed that well-peer mentored athletes were significantly more satisfied than their non-peer mentored counterparts in terms of individual performance, personal dedication, team task contribution, team social contribution, team integration, ethics, ability utilisation and training and instruction. Overall, the findings suggest that athletes who are well-peer mentored by a teammate perceive higher satisfaction levels with various aspects of their athletic experience than athletes who are not peer mentored by a teammate. Given these positive findings, practitioners (i.e., coaches, sport psychology consultants) should inform athletes on the benefits of peer-to-peer mentoring. The practical implications of the results and strategies to promote peer athlete mentoring relationships in sport are highlighted. 相似文献
193.
Abbie E. Smith-Ryan Eric T. Trexler Hailee L. Wingfield Malia N.M. Blue 《Journal of sports sciences》2016,34(21):2038-2046
The purpose of this study was to evaluate two practical interval training protocols on cardiorespiratory fitness, lipids and body composition in overweight/obese women. Thirty women (mean ± SD; weight: 88.1 ± 15.9 kg; BMI: 32.0 ± 6.0 kg · m2) were randomly assigned to ten 1-min high-intensity intervals (90%VO2 peak, 1 min recovery) or five 2-min high-intensity intervals (80–100% VO2 peak, 1 min recovery) or control. Peak oxygen uptake (VO2 peak), peak power output (PPO), body composition and fasting blood lipids were evaluated before and after 3 weeks of training, completed 3 days per week. Results from ANCOVA analyses demonstrated no significant training group differences for any primary variables (P > 0.05). When training groups were collapsed, 1MIN and 2MIN resulted in a significant increase in PPO (?18.9 ± 8.5 watts; P = 0.014) and time to exhaustion (?55.1 ± 16.4 s; P = 0.001); non-significant increase in VO2 peak (?2.36 ± 1.34 ml · kg?1 · min?1; P = 0.185); and a significant decrease in fat mass (FM) (??1.96 ± 0.99 kg; P = 0.011). Short-term interval exercise training may be effective for decreasing FM and improving exercise tolerance in overweight and obese women. 相似文献
194.
The main purpose of this article is to advance an alternative perspective on the relationship between intrinsic and extrinsic motivation, and in particular to examine critically the assertion that these processes are antagonistic such that the will to learn for its own sake is inhibited by the presence of extrinsic, tangible rewards and incentives such as school grades. The presumption of an antagonistic relationship largely depends on the theoretical perspective adopted. An alternative interpretation based on need achievement theory leads to distinctly different conclusions. Exploring this new perspective allows one to identify both the conditions under which intrinsic motives may coexist with extrinsic motives as well as to consider some of the means by which intrinsic motives and caring about learning can be stimulated in their own right in school settings. 相似文献
195.
Objectives: Development of evidence-based methods of Paralympic classification requires research quantifying the relative strength of association between ratio-scaled measures of impairment and athletic performance. The purpose of this study was to quantify the extent to which muscle strength affects running performance in runners with and without brain impairment. Design: Cross-sectional study. Methods: Participants were 41 male runners: 13 with brain impairments (RBI) and 28 non-disabled (NDR). All participants completed a maximal 60-m sprint and a novel battery of three lower limb isometric strength tests. Results: RBI showed significantly lower strength scores compared with NDR on the more affected side in leg flexion (176 vs. 243?N), leg extension (993 vs. 1661?N) and plantarflexion (824 vs. 1457?N). Significant differences were also seen on the less affected side in plantarflexion (1072 vs. 1508?N). RBI were significantly slower in the acceleration phase (0–15?m) (3.2?s?±?0.3?vs. 2.8?s?±?0.2) and top speed phase (30?60?m) (4.3?s?±?0.6?vs. 3.8?s?±?0.3). Correlation analysis showed stronger relationships between strength and running performance in RBI than NDR; however, the correlations were not significant. Conclusions: This study evaluated measures to assess strength for the purposes of classification and found that the measures were significantly different in RBI compared with NDR indicating the tests were able to capture strength impairment in this population. This study indicates that strength may be an important impairment type to assess in this population, as impairments of muscle strength may influence the outcome of running performance in athletes with more severe impairments. 相似文献
196.
Carol E. Vreeland Kristine M. Alpi Caitlin A. Pike Elisabeth E. Whitman Suzanne Kennedy-Stoskopf 《Journal of the Medical Library Association》2016,104(2):100-108
Objective
“One Health” is an interdisciplinary approach to evaluating and managing the health and well-being of humans, animals, and the environments they share that relies on knowledge from the domains of human health, animal health, and the environmental sciences. The authors'' objective was to evaluate the extent of open access (OA) to journal articles in a sample of literature from these domains. We hypothesized that OA to articles in human health or environmental journals was greater than access to animal health literature.Methods
A One Health seminar series provided fifteen topics. One librarian translated each topic into a search strategy and searched four databases for articles from 2011 to 2012. Two independent investigators assigned each article to human health, the environment, animal health, all, other, or combined categories. Article and journal-level OA were determined. Each journal was also assigned a subject category and its indexing evaluated.Results
Searches retrieved 2,651 unique articles from 1,138 journals; 1,919 (72%) articles came from 406 journals that contributed more than 1 article. Seventy-seven (7%) journals dealt with all 3 One Health domains; the remaining journals represented human health 487 (43%), environment 172 (15%), animal health 141 (12%), and other/combined categories 261 (23%). The proportion of OA journals in animal health (40%) differed significantly from journals categorized as human (28%), environment (28%), and more than 1 category (29%). The proportion of OA for articles by subject categories ranged from 25%–34%; only the difference between human (34%) and environment (25%) was significant.Conclusions
OA to human health literature is more comparable to animal health than hypothesized. Environmental journals had less OA than anticipated.Keywords (Medical Subject Headings) Publishing, Periodicals as Topic, Access to Information, Veterinary Medicine, Environment, Environmental Health, Medicine“One Health” is an integrated, transdisciplinary approach to solve complex problems at the diverse interfaces shared by humans, animals, and the environment [1]. The One Health approach to evaluating and managing the health and well-being of humans, animals, and the environments that they share relies on knowledge from the domains of human health, animal health, and the environmental sciences. Although there is a growing body of literature about the development of the One Health concept as documented by Pepper, Carrigan, Shurtz, and Foster [2], this literature is not the same as the combination of literature from the three domains that is applied in service of One Health. Every discipline related to One Health has its unique mindset and language, with corresponding lists of acronyms that are frequently an impediment to effective communication across the participating professions. Relevant papers guiding a One Health approach may never specifically use “One Health” as a term or concept.To promote better communication and collaboration among health professionals and environmental scientists, a public monthly One Health Intellectual Exchange Group (IEG) hosted by the North Carolina Biotechnology Center was launched in 2009. In 2011, faculty from the North Carolina State University College of Veterinary Medicine, University of North Carolina''s Gillings School for Global Public Health, Duke Global Health Institute, and Nicholas School of the Environment at Duke University expanded the IEG series into a weekly seminar course with eight One Health focus areas [3]. The eight focus area modules were the following: an introduction to One Health; environmental health and ecology; the human and animal bond; zoonoses and emerging infectious diseases; food and water safety; disease surveillance, informatics, and disaster preparedness; benefits of comparative medicine; and policy and education (Appendix A, online only). Each seminar speaker recommended papers to read prior to the session to provide a foundation for the topic because student backgrounds and majors were quite diverse. Represented student majors included master''s of public health, master''s of animal science, doctor of veterinary medicine, graduate-level environmental sciences, and undergraduate-level biochemistry, engineering, and biology.Open access (OA) to relevant literature is very important to scholars and practitioners working on interdisciplinary problems. The One Health Proof of Concept Workgroup found that few studies assess outcomes in human, animal, and environmental spheres simultaneously [4], making it important to be able to access articles from each of the three domains to get a more complete picture.The objective of this study was to evaluate the extent of OA to journal articles in a sample of literature relevant to One Health from the human, animal, and environmental domains. Working in a college of veterinary medicine and supporting faculty, staff, and students addressing interdisciplinary problems under the One Health umbrella [5], the authors were familiar with the extent of OA in human biomedical and public health literature and the literature of veterinary medicine but were less familiar with environmental journals. In light of general availability of environmental information and OA to publications such as Environmental Health Perspectives, we thought it likely that environmental literature would be relatively open compared to the other subject areas. Therefore, we hypothesized OA to articles from human health or environmental journals was greater than access to animal health literature. We chose to look at article-level subject categorization and access, as well as journal-level categorization and access, because they might differ. Article-level access relates more to authors'' decisions about OA for a content domain, while journal-level access and subject categorization are driven by publishers and associations. Understanding the distinction and having data would inform our efforts to promote increased OA to this literature. 相似文献197.
Acevedo MC 《Child abuse & neglect》2000,24(1):111-127
OBJECTIVE: To assess: (1) ethnic differences in the health-risk behaviors, mental health problems, and adverse parenting beliefs during pregnancy of low-income Mexican American and European American women; and, (2) the extent to which these risks varied with levels of acculturation among low-income Mexican American women. METHOD: Participants were 594 primiparous, low-income, urban women. A cross-sectional design was used to compare the 331 Mexican American women to the 263 European American. Language was used to assess the level of acculturation of the Mexican American women. Interviews were used to evaluate health-risk behaviors, mental health problems, and adverse parenting beliefs. RESULTS: In comparison to European American women, Mexican American women were at lower risk for cigarette smoking during pregnancy and higher risk for adverse parenting beliefs. Among Mexican American women, Spanish speakers were at lower risk for cigarette smoking and mental health problems during pregnancy, and higher risk for adverse parenting beliefs than bilingual and English speakers. CONCLUSIONS: The findings indicate that ethnic differences in cigarette smoking and parenting beliefs during pregnancy were concentrated on the less acculturated, low-income, and primarily unmarried Spanish speaking Mexican American women. Moreover, acculturation is differentially related to cigarette smoking and parenting beliefs. Therefore, acculturation needs to be considered in the development of preventive interventions in order to appropriately target the specific needs of different sub-populations of Mexican Americans. 相似文献
198.
Research suggests growth mindset, or the belief that knowledge is acquired through effort, may enhance women’s sense of belonging in male-dominated disciplines, like computing. However, other research indicates women who spend a great deal of time and energy in technical fields experience a low sense of belonging. The current study assessed the benefits of a growth mindset on women’s (and men’s) sense of intellectual belonging in computing, accounting for the amount of time and effort dedicated to academics. We define “intellectual belonging” as the sense that one is believed to be a competent member of the community. Whereas a stronger growth mindset was associated with stronger intellectual belonging for men, a growth mindset only boosted women’s intellectual belonging when they did not work hard on academics. Our findings suggest, paradoxically, women may not benefit from a growth mindset in computing when they exert a lot of effort. 相似文献
199.
A theoretical model of nonscience majors' motivation to learn science was tested by surveying 369 students in a large‐enrollment college science course that satisfies a core curriculum requirement. Based on a social‐cognitive framework, motivation to learn science was conceptualized as having both cognitive and affective influences that foster science achievement. Structural equation modeling was used to examine the hypothesized relationships among the variables. The students' motivation, as measured by the Science Motivation Questionnaire (SMQ), had a strong direct influence on their achievement, as measured by their science grade point average. The students' motivation was influenced by their belief in the relevance of science to their careers. This belief was slightly stronger in women than men. Essays by the students and interviews with them provided insight into their motivation. The model suggests that instructors should strategically connect science concepts to the careers of nonscience majors through such means as case studies to increase motivation and achievement. © 2006 Wiley Periodicals, Inc. J Res Sci Teach 44: 1088–1107, 2007 相似文献
200.