排序方式： 共有66条查询结果，搜索用时 31 毫秒
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Francisco Cuenca-Fernández Gracia López-Contreras Luis Mourão Karla de Jesus Kelly de Jesus Rodrigo Zacca 《Journal of sports sciences》2019,37(4):443-451
This study aimed to assess the effects of post-activation potentiation in the strength related variables of a kick start. Thirteen competitive swimmers performed three kick starts after a standardized warm up (denoted USUAL) and another after inducing post-activation through five isotonic repetitions on an eccentric flywheel (denoted PAP). A T-test was used to quantify differences between USUAL and PAP warm up. The best trial of each subject achieved by natural conditions (denoted PEAK) was compared with data obtained after PAP. An instrumented starting block with independent triaxial force plates, collected the strength variables related with the impulse at take off. Improvements in the vertical components of force were observed after PAP compared with USUAL, meanwhile no differences were detected on the horizontal components of it. The velocity at take off was higher after PAP compared with USUAL (4.32 ± 0.88 vs 3.93 ± 0.60 m*s-1; p = 0.02). No differences in force or velocity were detected comparing PAP with PEAK (4.13 ± 0.62 m*s-1, p = 0.11). The PAP warm-up increased vertical force and it was transferred to a higher resultant velocity at take-off. This improvement would equal the best result possible obtained in natural conditions after some trials. 相似文献
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De Jesus K Figueiredo P De Jesus K Pereira F Vilas-Boas JP Machado L Fernandes RJ 《Journal of sports sciences》2012,30(7):715-723
During water polo matches, players use different front crawl styles. The purpose of this study was to conduct a kinematic analysis of three water polo front crawl styles: front crawl with head under water, front crawl with head above water, and front crawl when leading the ball. Ten proficient water polo players performed 3 × 15 m sprints in each front crawl style, which were recorded three-dimensionally by two surface and four underwater cameras. The results showed no differences in performance and several kinematic characteristics among the water polo front crawl styles. However, front crawl when leading the ball showed shorter stroke length and greater stroke frequency. Front crawl with head underwater presented greater maximal finger depth and elbow angle at mid-stroke position. Front crawl with head above water and when leading the ball showed greater trunk obliquity and maximal depth of right and left foot, and shorter kick stroke frequency. The findings suggest that proficient players learn to master front crawl with head above water to achieve top velocity. Despite the common use of the front crawl with head underwater as the basis for water polo fast displacement, coaches should emphasize the use of the specific water polo styles to attain high performance. 相似文献
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Despite a spate of media attention in recent years and implications for both work and family relationships, communication scholars have yet to study work-spouse relationships. Since popular press sources have often focused on the nature of and propriety of such relationships, the purpose of this study was to empirically examine how work spouses characterized their relationships. We analyzed 269 participants’ open-ended responses to a survey, which yielded five categories: (a) characteristics of a work spouse, (b) conditions for the work-spouse relationship, (c) characteristics of the work-spouse relationship, (d) functions of work spouses, and (e) ways of managing the work-spouse relationship. From this analysis, we construct a definition of the relationship and chart a course of future research for communication scholars. 相似文献
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Kizzy Albritton Rachel E. Mathews Karla Anhalt 《Journal of educational and psychological consultation》2013,23(4):444-472
ABSTRACTEarly childhood mental health consultation (ECMHC) is a framework that continues to expand as students’ social-emotional needs emerge at younger ages. The present systematic review examines the extant literature surrounding the use of ECMHC and behavioral consultation in addressing mental health concerns and challenging behaviors in preschool students. Findings associated with this systematic review suggest that ECMHC could be a promising practice for targeting internalizing and externalizing behavioral concerns in prekindergarten students across a variety of settings. However, more research is needed in the areas of mental health/behavioral consultation and disciplinary disproportionality, as well as on the impact of such practices on preschool children of color. Implications for school psychologists are discussed, as are disciplinary practices when providing ECMHC and behavioral consultation services with students of diverse racial, ethnic, and cultural backgrounds. 相似文献
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Belmiro Freitas De Salles Marcos Doederlein Polito Karla Fabiana Goessler Pietro Mannarino Thiago Torres Matta Roberto Simão 《European Journal of Sport Science》2016,16(8):927-931
In its last position stand about strength training, the American College of Sports Medicine recommends a rest interval (RI) between sets ranging between 1 and 3?min, varying in accordance with the objective. However, there is no consensus regarding the optimal recovery between sets, and most studies have investigated fixed intervals. Therefore, the aim of this study was to analyse the effects of fixed versus self-suggested RI between sets in lower and upper body exercises performance. Twenty-seven healthy subjects (26?±?1.5; 75?±?15?kg; 175?±?12?cm) were randomly assigned into two groups: G1: lower body exercises and G2: upper body exercises. Squat and leg press 1 repetition maximum (1RM) were tested for the G1 and bench press and biceps curl 1RM for G2. After the 1RM tests, both groups performed three sets to concentric failure with 75% of 1RM in combination with different RIs (2?min or self-suggested) on separate days and the exercises performance was evaluated by the number of repetitions. The results demonstrated no significant differences in the number of repetitions between 2?min and self-suggested RIs that presented similar reductions with the sets progression. It was also shown that the self-suggested RI spent less time recovering than the 2?min RI group on average. This suggests that for individuals with previous experience, the self-suggested RI can be an effective option when using workloads commonly prescribed aiming hypertrophy. Also, the self-suggested RI can reduce the total training session duration, which can be a more time-effective strategy. 相似文献
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Educational programs are seen as a vehicle for improving the educational experiences and life outcomes for youthful offenders.
In 1998 North Carolina started the Workplace and Community Transition Youth Offender Program (YOP). The program offers youth
post-secondary educational courses. Our study examines 2007–2009 data from YOP youth participating in the program. Using students’
voices our study shows that YOP not only decreases recidivism drastically, but has a personal impact in the youth participants’
lives. YOP provides a space of change that is not prison or a traditional college. The hybrid figured world provides an opportunity
for African American male youth to re/author themselves creating new hybrid identities. The youth author themselves as students
versus inmates. These new identities and educational competencies have potentially long term benefits for youth offenders
and for communities. 相似文献
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