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61.
Max R. Paquette Brian K. Schilling Joshua D. Bravo Shelby A. Peel Yuhua Li Robert J. Townsend 《Research quarterly for exercise and sport》2017,88(1):44-51
Understanding the effects of training in different footwear on sporting performance would be useful to coaches and athletes. Purpose: This study compared the effects of computerized agility training using 3 types of footwear on change-of-direction and balance performance in young adults. Method: Thirty recreationally active young adults (Mage = 22.8 ± 3.1 years; Mheight = 1.71 ± 0.7 m; Mbodymass = 73.4 ± 10.3 kg) were randomly assigned to a 6-week computerized agility training intervention in 1 of 3 footwear groups (n = 10/group): barefoot, minimal footwear, or traditional shoes. Participants had no previous barefoot or minimal-footwear training experience. Dependent variables included change-of-direction test time to completion, Star Excursion Balance Test, and single-leg stability evaluation. Testing was performed at the start of the training program, after 2 weeks, after 4 weeks, and at the end of the training program. Results: No group or time interactions were found for any of the dependent variables. Time main effects were observed for the performance measures of change of direction, Star Excursion, and single-leg-with-eyes-open stability evaluation. Participants improved in all 3 tests as early as 2 weeks into the intervention, with improvements continuing through the entire 6-week intervention. Conclusions: The lack of interaction and footwear effects suggests that agility and balance improvements during foot agility training are independent of footwear in a recreationally active young-adult population. Computerized agility training improves change-of-direction and balance performance within 2 weeks of training implementation. Future studies should consider footwear training effects in different populations, including frail older adults and athletes. 相似文献
62.
63.
Justin M. Guagliano Natalie J. Updyke Natalia V. Rodicheva Sara K. Rosenkranz David A. Dzewaltowski Chelsey R. Schlechter 《Research quarterly for exercise and sport》2017,88(3):352-357
Purpose: This study investigated the effect of summer camp session context on Russian girls’ physical activity (PA). Method: Girls (n = 32, Mage = 10.7 years, SD = 0.6 years) from a resident summer camp taking place in the Vologda Region of Russia were exposed to 1 session context/day (i.e., free play, organized with no choice, organized with choice) on Wednesday, Thursday, and Friday for 3 weeks, with the context order counterbalanced across the 3 weeks. The organized session sport/game changed weekly. The primary outcome was accelerometer-assessed PA. Repeated-measures mixed models were used to analyze all outcome data. Results: Findings showed that girls spent a greater percentage of session time (%time) in moderate-to-vigorous PA (p < .001; effect sizes between free play and organized with no choice and organized with choice, respectively = .60, .42) and moderate PA (p < .001; effect size = .57, .39) and a lower %time in light PA (p < .001; effect size = .55, .52) in organized PA contexts compared with free play. Conclusions: This study provides novel findings in a Russian setting, suggesting that a well-planned, organized camp session can elicit higher PA levels in girls, relative to a free-play session. 相似文献
64.
Roy T. H. Cheung Rodney Y. L. Wong Tim K. W. Chung R. T. Choi Wendy W. Y. Leung Diana H. Y. Shek 《Sports biomechanics / International Society of Biomechanics in Sports》2017,16(2):238-247
Compared to competitive runners, recreational runners appear to be more prone to injuries, which have been associated with foot strike patterns. Surprisingly, only few studies had examined the foot strike patterns outside laboratories. Therefore, this study compared the foot strike patterns in recreational runners at outdoor tracks with previously reported data. We also investigated the relationship between foot strike pattern, speed, and footwear in this cohort. Among 434 recreational runners analysed, 89.6% of them landed with rearfoot strike (RFS). Only 6.9 and 3.5% landed with midfoot and forefoot, respectively. A significant shift towards non-RFS was observed in our cohort, when compared with previously reported data. When speed increased by 1 m/s, the odds of having forefoot strike and midfoot strike relative to RFS increased by 2.3 times and 2.6 times, respectively. Runners were 9.2 times more likely to run with a forefoot strike in minimalists compared to regular running shoes, although 70% of runners in minimalists continued to use a RFS. These findings suggest that foot strike pattern may differ across running conditions and runners should consider these factors in order to mitigate potential injury. 相似文献
65.
Jaymee R. Shell Shawn M. K. Robbins Philippe C. Dixon Philippe J. Renaud René A. Turcotte Tom Wu 《Sports biomechanics / International Society of Biomechanics in Sports》2017,16(3):313-324
The forward skating start is a fundamental skill for male and female ice hockey players. However, performance differences by athlete’s sex cannot be fully explained by physiological variables; hence, other factors such as skating technique warrant examination. Therefore, the purpose of this study was to evaluate the body movement kinematics of ice hockey skating starts between elite male and female ice hockey participants. Male (n = 9) and female (n = 10) elite ice hockey players performed five forward skating start accelerations. An 18-camera motion capture system placed on the arena ice surface captured full-body kinematics during the first seven skating start steps within 15 meters. Males’ maximum skating speeds were greater than females. Skating technique sex differences were noted: in particular, females presented ~10° lower hip abduction throughout skating stance as well as ~10° greater knee extension at initial ice stance contact, conspicuously followed by a brief cessation in knee extension at the moment of ice contact, not evident in male skaters. Further study is warranted to explain why these skating technique differences exist in relation to factors such as differences in training, equipment, performance level, and anthropometrics. 相似文献
66.
Andrea R. Milner Toni A. Sondergeld Abdulkadir Demir Carla C. Johnson Charlene M. Czerniak 《Journal of Science Teacher Education》2012,23(2):111-132
The impact of No Child Left Behind (NCLB) mandated state science assessment on elementary teachers’ beliefs about teaching
science and their classroom practice is relatively unknown. For many years, the teaching of science has been minimized in
elementary schools in favor of more emphasis on reading and mathematics. This study examines the dynamics of bringing science
to the forefront of assessment in elementary schools and the resulting teacher belief and instructional shifts that take place
in response to NCLB. Results indicated that teachers’ beliefs about teaching science remained unchanged despite policy changes
mandated in NCLB. Teacher beliefs related to their perceptions of what their administrators and peer groups’ think they should
be doing influenced their practice the most. Most teachers reported positive feelings and attitudes about science and reported
that their students had positive feelings and attitudes about science; however, teachers reported teaching science less as
a result of NCLB. Implications for elementary science education reform and policy are discussed. 相似文献
67.
Sam Pickering teaches English at the University of Connecticut 相似文献
68.
Ressol R.SHAKIR 《浙江大学学报(A卷英文版)》2010,11(4):294-304
Evidence gained from previous field tests conducted on drilled shaft foundation shows that using drilling slurries to stabilize a borehole during the construction may influence the interfacial shear strength. This paper deals with an exhaustive study of the effects of drilling slurries at the contact between soil and concrete. This study involved adapting a simple shear apparatus and performing approximately 100 experimental tests on the interaction between two types of soils; clay and sandy clay and five specimens of concrete with different surface shapes. It also involved using bentonite and polymer slurries as an interface layer between soil and concrete. Results showed that an interface layer of bentonite slurry between clay and concrete decreases the interfacial shear strength by 23% and as an interface layer between sandy clay and concrete, bentonite increases interfacial shear strength by 10%. Using polymer slurry as an interface layer between clay and concrete decreases the interfacial shear strength by 17% while using it as an interface layer between sandy clay and concrete increases the interfacial shear strength by 10%. Fur- thermore, the data show that using bentonite and polymer slurry as an interface layer between clay and concrete decreases the sliding ratio by 50% to 60%, while increasing the sliding ratio by 44% to 56% when these are used as an interface layer between sandy clay and concrete. 相似文献
69.
The efficacy of a cognitive-based arithmetic problem-solving model (Dinnel, Glover, & Halpain, in press; Dinnel, Glover, & Ronning, 1984) was tested using 989 students with learning disabilities. Comprehensive neuropsychological test battery information was used to predict composite arithmetic test performance as a means of examining the utility of this model. Results of this study offer support for Dinnel et al.'s (Dinnel, Glover, & Halpain, in press; Dinnel, Glover, & Ronning, 1984) model in accounting for arithmetic performance under continuous visual stimulus conditions. However, these data indicate a more complex neuropsychological underpinning to arithmetic performance in both visual and aural stimulus conditions. The neuropsychological aspects of arithmetic problem solving were discussed in relationship to this cognitive-based model. 相似文献
70.
N. Chandra Shekhar K. Venkatasubbaiah N. R. Kandukuria 《European Journal of Engineering Education》2012,37(6):575-591
Measuring overall service quality (OSQ) is gaining prominence in higher education due to the increased competition among engineering education institutions (EEIs) and growing awareness about value for money among the public. Determination of OSQ on certain institutional aspects is done by various agencies throughout the world. Each system uses a different set of weighted indicators to measure the overall service quality of institutions. Five service quality factors, namely professionalism, integrated education, facilities, responsiveness and empathy are considered in the study. Trapezoidal fuzzy numbers are used to determine the aggregate weights of the factors to handle the vagueness present in the linguistic values of the stakeholders’ subjective opinions. Final weights of the factors are assessed by taking the distances of each factor between Fuzzy Positive Ideal Rating and Fuzzy Negative Ideal Rating. An illustrative study is presented to determine the OSQ of EEIs. The results help to focus on the factors which need immediate attention to enhance the quality of EEIs. 相似文献