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1.
肌酸激酶与力量训练的实验研究 总被引：4，自引：0，他引：4
以速滑运动员为研究对象,观察不同训练水平运动员进行不同强度和不同训练时间的力量训练前后,其体内肌酸激酶(CK)活性的变化.结果表明:只有达到一定训练强度,才可引起体内CK活性的显著变化;不同水平运动员进行大强度力量训练后,均可引起体内CK活性大幅度升高;不同水平运动员进行相同强度(80%、90%)的力量训练后,训练水平较高者较训练水平较低者CK值上升幅度小;相同级别运动员进行不同强度(80%、90%)的力量训练后,训练强度大者较训练强度小者CK活性上升幅度大;相同水平运动员以相同的大强度进行力量训练后,较长时间训练者比短时间训练者,其体内CK值上升得小.进而说明选择测定训练前后CK活性值来判定运动员对力量训练的反应,是较为敏感实用的指标之一. 相似文献
2.
Xier Luo Yu Zhou Bing Zhang Yi Zhang Xiaobo Wang Tong Feng Zhipeng Li Kuiqing Cui Zhiqiang Wang Chan Luo Hui Li Yanfei Deng Fenghua Lu Jianlin Han Yongwang Miao Huaming Mao Xiaoyan Yi Cheng Ai Shigang Wu Alun Li Zhichao Wu Zijun Zhuo Do Da Giang Bikash Mitra Mohammad Farhad Vahidi Shahid Mansoor Sahar Ahmed Al-Bayatti Eka Meutia Sari Neena Amatya Gorkhali Sigit Prastowo Laiba Shafique Guoyou Ye Qian Qian Baoshan Chen Deshun Shi Jue Ruan Qingyou Liu 《国家科学评论(英文版)》2020,7(3):686
Domesticated buffaloes have been integral to rice-paddy agro-ecosystems for millennia, yet relatively little is known about the buffalo genomics. Here, we sequenced and assembled reference genomes for both swamp and river buffaloes and we re-sequenced 230 individuals (132 swamp buffaloes and 98 river buffaloes) sampled from across Asia and Europe. Beyond the many actionable insights that our study revealed about the domestication, basic physiology and breeding of buffalo, we made the striking discovery that the divergent domestication traits between swamp and river buffaloes can be explained with recent selections of genes on social behavior, digestion metabolism, strengths and milk production. 相似文献
3.
Suzana Matheus Pereira Caroline Ruschel Marcel Hubert Leandro Machado Helio Roesler Ricardo Jorge Fernandes 《Journal of sports sciences》2015,33(19):2006-2015
This study aimed to analyse the kinematic, kinetic and electromyographic characteristics of four front crawl flip turn technique variants. The variants distinguished from each other by differences in body position (i.e. dorsal, lateral, ventral) during rolling, wall support, pushing and gliding phases. Seventeen highly trained swimmers (17.9 ± 3.2 years old) participated in interventional sessions and performed three trials of each variant, being monitored with a 3-D video system, a force platform and an electromyography (EMG) system. Studied variables: rolling time and distance, wall support time, push-off time, peak force and horizontal impulse at wall support and push-off, centre of mass horizontal velocity at the end of the push-off, gliding time, centre of mass depth, distance, average and final velocity during gliding, total turn time and electrical activity of Gastrocnemius Medialis, Tibialis Anterior, Biceps Femoris and Vastus Lateralis muscles. Depending on the variant, total turn time ranged from 2.37 ± 0.32 to 2.43 ± 0.33 s, push-off force from 1.86 ± 0.33 to 1.92 ± 0.26 BW and centre of mass velocity during gliding from 1.78 ± 0.21 to 1.94 ± 0.22 m · s?1. The variants were not distinguishable in terms of kinematical, kinetic and EMG parameters during the rolling, wall support, pushing and gliding phases. 相似文献
4.
Bülent 《浙江大学学报(A卷英文版)》2010,11(2):106-114
In this study, an electro-mechanical valve （EMV） system for the intake valve ofa fottr stroke, single cylinder, overhead valve and spark ignition （SI） engine was designed and constructed. An engine with the EMV system and a standard engine were tested to observe the effects of the EMV on engine performance and emissions at different speeds under full load. The EMV engine showed improved engine power, engine torque and break specific fuel consumption （BSFC）. A 66% decrease in CO emissions was also obtained with the EMV system, but hydrocarbons （HC） and NOx emissions increased by 12% and 13% respectively. 相似文献
5.
Mikhail Santos Cerqueira Jose Diego Sales Do Nascimento Daniel Germano Maciel Jean Artur Mendonca Barboza Wouber Herickson De Brito Vieira 《运动与健康科学(英文)》2020,9(2):152-159
Purpose:To investigate whether blood flow restriction(BFR) without concomitant exercise mitigated strength reduction and atrophy of thigh muscles in subjects under immobilization for lower limbs.Methods:The following databases were searched:PubMed,CINAHL,PEDro,Web of Science,Central,and Scopus.Results:The search identified 3 eligible studies,and the total sample in the identified studies consisted of 38 participants.Isokinetic and isometric torque of the knee flexors and extensors was examined in 2 studies.Cross-sectional area of thigh muscles was evaluated in 1 study,and thigh girth was measured in 2 studies.The BFR protocol was 5 sets of 5 min of occlusion and 3 min of free flow,twice daily for approximately 2 weeks.As a whole,the included studies indicate that BFR without exercise is able to minimize strength reduction and muscular atrophy after immobilization.It is crucial to emphasize,however,that the included studies showed a high risk of bias,especially regarding allocation concealment,blinding of outcome assessment,intention-to-treat analyses,and group similarity at baseline.Conclusion:Although potentially useful,the high risk of bias presented by original stodies limits the indication of BFR without concomitant exercise as an effective countermeasure against strength reduction and atrophy mediated by immobilization. 相似文献
6.
Taís Rieping Guilherme Eustáquio Furtado Matheus Uba Chupel Juan C. Colado Eef Hogervorst 《Research quarterly for exercise and sport》2019,90(1):36-45
Purpose: The aim of this study was to test the effects of chair-based exercise programs on salivary stress hormones, physical fitness, and functional autonomy of institutionalized older women. Method: In total, 47 participants (80 ± 8.04 years old) were recruited and allocated into three groups: chair-based aerobic exercises (CAE, n = 19), chair-based elastic-band strength exercises (CSE, n = 15), and a control group (CG, n = 13). A 14-week exercise intervention was done for the CAE and CSE groups, two times per week, in no consecutive days. Members of the CG did not participate in any type of exercise but kept their regular lifestyle. Fear of falling, autonomy, physical fitness, salivary cortisol, and alpha-amylase levels were assessed before and after the intervention. Results: The CAE group improved upper and lower body strength, agility–dynamic balance, and autonomy, with fear of falling decreasing significantly (p < .05, moderate effect size). Both exercise groups showed a trend toward an increase in salivary alpha-amylase levels (CAE = 43%, d = .31, and CSE = 44%, d = .41). Conclusion: Both exercise programs were able to improve functional autonomy, even in elders older than 80 years of age. It might be interesting to investigate the effectiveness of combining both aerobic and strength exercises in a unique protocol. The modulation effect of exercise in the hormonal responses needs to be further explored. 相似文献
7.
Barreto Lucas Passos Rodrigues Adriana Araújo Dutra de Oliveira Giordanna Camilla Bié de Almeida Laila Thayanne Gomes Felix Matheus Augusto Campelo Silva Penha de Souza Quadros Ana Luiza Macedo Andrea Mara Mortimer Eduardo Fleury 《Research in Science Education》2021,51(1):135-152
Research in Science Education - This research draws on Legitimation Code Theory (LCT) to understand the epistemic dimension of the higher education classroom discourse of a professor who is well... 相似文献
8.
AbstractRecent significant changes in technology such as Artificial Intelligence (AI) and big data analysis have a wide impact in many areas of human societies, not least in education. Advances in efficiency of new technologies, with impacts in renewable energy and transport affected by environmental concerns and climate change mitigation, demand a reassessment and adjustment of the industrial structure of the economy. Technological advances enhancing creativity and analytical skills mean people must learn and adapt to a fast-changing economic environment. This paper present some key changes in Australian educational areas in recent years that are important and relevant to the subject of education innovation and philosophy to achieve outcomes in training and sustainable economic development, as anticipated by the community and government. Education courses and curricula in many countries have been transformed by technological advance. It is the swift incorporation of new technologies that best prepares students for the dynamics of economic and social change. Even though technological responsiveness is not a new phenomenon, it is established that the teaching methods found to be most successful include complementary and supplemental courses producing multi-skilled and creative graduates. These courses are delivered with significant emphasis upon self-development skills and are less focused upon traditional content. A move toward horizontal focus and a student-centric balance is the current trend, displacing vertical over-specialisation of learning. Yet, the central role of educator is seen as still appropriate and necessary where the aim is to equip graduates with creative and adaptive skills. 相似文献
9.
Drawing from data gathered in South Western Madagascar in 2011, the work explores the combination of poverty and traditional gender roles as a critical factor in determining unequal school access among young people from semi-nomadic fishing communities. It demonstrates that from the age of early puberty, most boys go fishing with their fathers and brothers whilst most girls from the same families work at home. In contrast to the school systems observed in many developing society contexts, which demonstrate female marginalisation, in South Western Madagascar both boys and girls are marginalised. Instruments of global policy designs, such as positive discrimination for girls, seem ill-suited to resolve the problem. Instead, the authors call for a more tailored and context-specific approach to address the particular challenges amongst semi-nomadic fishing communities in Madagascar. 相似文献
10.
This paper examines social coordination by the Brazilian Black Movement in the area of Brazilian education. It explains how these developments relate to the construction of race-based public education policies in the country. Focus goes to the process of creation and implementation of law 10.639 in Brazilian Basic education. Using the concept ‘diffuse governance’, the argument is made that at present it are the multiple actions by the Brazilian Black Movement, in diverse arenas of dispute, and interacting with a range of actors, that enable us to understand the social coordination/regulation in the process of constructing and implementing Law 10.639. 相似文献