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灵敏性是篮球技能的灵魂,篮球运动员脚步动作灵敏性决定脚步移动能力,灵敏性是决定运动员反应速度、脚步移动速度以及移位能力的重要因素。为研究绳梯训练对篮球运动员脚步移动能力的影响,运用文献资料法、专家访谈法、实验法等对篮球运动员进行8周绳梯训练和常规脚步移动训练的灵敏性对比实验研究。实验结果表明,采用不同训练手段进行灵敏训练的效果存在显著性差异,采用绳梯训练手段的实验组脚步动作灵敏性和脚步移动技术能力获得大幅度提高,绳梯训练对发展篮球运动员的灵敏性具有更好的效果。 相似文献
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背景:灵敏素质是与运动和运动机能增强相关的标志之一,良好的灵敏素质可以有效预防生活中可能受到的伤害,小篮球对幼儿灵敏素质的影响尚无统一意见。目的:通过meta分析,探索小篮球对幼儿灵敏素质的影响,为幼儿体质研究提供研究证据。方法:以“幼儿”and“篮球”为检索主题词对中国知网、万方、维普数据库进行检索,检索时限为建库至2021年9月,根据纳入和排除标准排除不符合要求的文献,对所纳入的文献进行文献质量评价。若研究间异质性较高,首先逐一排除文献进行敏感性分析,若异质性仍然高则对可能的异质性因素进行亚组分析。meta分析软件采用Review Manager5.4。结果:meta分析结果显示与常规体育活动相比篮球运动对幼儿10m折返跑成绩提高了0.35s,(MD=-0.35,95 CI%:[-0.81~0.11]),结果没有统计学差异(P=0.14)。亚组分析发现4-5岁亚组与常规体育活动相比篮球运动提高了幼儿10m折返跑成绩0.17s,结果没有统计学差异(P=0.7);5-6岁亚组与常规体育活动相比小篮球训练提高了幼儿10m折返跑成绩0.66s,结果有统计学差异(P<0.01)。结论:篮球训练与常规体育活动相比可以有效提高幼儿的灵敏素质,但是不能否认常规体育活动对幼儿体质的发展的作用。 相似文献
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供应链敏捷性的以往研究忽视了供应链企业间竞合关系的存在,且集体横向竞合对供应链敏捷性的影响及其作用机制仍不清晰。本文基于动态能力理论、社会网络理论以及组织学习理论,深入探讨了集体横向竞合对公司供应链敏捷性的影响机制。采用Bootstrap检验方法对216份专业市场中大型企业的问卷开展实证研究发现：集体横向竞合能直接或间接地对供应链敏捷性产生正向且显著的影响。集体横向竞合与供应链敏捷性之间存在三条中介路径,其中网络嵌入性中介路径对供应链敏捷性的影响最大,其次是组织学习能力中介路径,而网络嵌入性与组织学习能力的链式中介路径对供应链敏捷性的影响最小,且网络嵌入性是集体横向竞合与组织学习能力之间的唯一中介。 相似文献
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《European Journal of Sport Science》2013,13(2):137-143
AbstractDorsiflexion sport shoes aim to increase jumping capacity and speed by means of a lower position of the heel in comparison with the forefoot, favouring additional stretching of the ankle plantar flexors. In previous studies, contradictory results have been found on the benefits of using this type of shoe. With the aim of comparing a dorsiflexion sport shoe model (DF) with a conventional sport shoe (CS), 41 participants performed a countermovement jump (CMJ) test and an agility test (MAT) with both models of shoe. There were no significant differences in the jump test [CS=35.3 cm (6.4) and DF=35.6 cm (6.4), P>0.05]. In the agility test, the conventional shoe obtained better results than the model with dorsiflexion with regard to time taken to complete the circuit [CS=6236 ms (540) and DF=6377 ms (507), P<0.05)]. In spite of producing pre-stretching of the plantar muscles, the DF sport shoes were not effective for improving either jump power or agility in a specific test. 相似文献
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Abstract In this study, we determined the specificity of a low frequency taekwondo training programme on physical fitness levels in adolescent females who receive limited physical education instruction (i.e. 2 days per week). Major components of physical fitness assessed were: skeletal muscle fitness (hand grip strength, bent arm hang, standing long jump, and isokinetic strength), flexibility (sit-and-reach test), speed and agility (10 × 5-m shuttle run), and cardiovascular fitness ([Vdot]O 2max and 20-m shuttle run). Changes in body composition were also assessed (dual X-ray absorptiometry, DXA). Participants were divided into two groups, a taekwondo training group (n = 21), which trained 50 min a day, 2 days per week for 12 weeks, and a control group (n = 10). Taekwondo training improved isokinetic strength, standing long jump, and sit-and-reach performance. Body fat mass and percent body fat were reduced. No changes in grip strength, bent arm hang time, speed and agility, or cardiorespiratory fitness were observed. Results indicate that low frequency taekwondo training in adolescent females produces beneficial changes in skeletal muscle fitness, flexibility, and body composition in a relatively short period of time. Consequently, this specific type of training can be useful to female adolescents in structured school environments where physical education classes are limited and there is little free time for physical activity. 相似文献
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AbstractThe purpose of this study was to determine the effects of training change-of-direction speed and small-sided games on performance in the Planned-AFL agility test and reactive agility. Twenty-five elite-standard U-18 Australian Rules football players were randomly allocated either to a change-of-direction group or a small-sided games group. Players participated in one or two 15-min sessions per week with 11 sessions conducted over a 7-week period during the season. Tests conducted immediately before and after the training period included the Planned-AFL agility test and a video-based reactive agility test specific to Australian Rules football. The reactive agility test variables were total time, decision time and movement response time. The small-sided games group improved total time (P = 0.008, effect size = 0.93), which was entirely attributable to a very large reduction in decision time (P < 0.001, effect size = 2.32). Small-sided games produced a trivial change in movement response time as well as in the Planned-AFL agility test (P > 0.05). The change-of-direction training produced small to trivial changes in all of the test variables (P > 0.05, effect size = 0–0.2). The results suggest that small-sided games improve agility performance by enhancing the speed of decision-making rather than movement speed. The change-of-direction training was not effective for developing either change-of-direction speed as measured by the Planned-AFL test or reactive agility. 相似文献
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Mostafa Zarei Hamed Abbasi Abdolhamid Daneshjoo Tohid Seif Barghi Nikki Rommers Oliver Faude 《Journal of sports sciences》2018,36(21):2447-2454
This study examined the long-term effects of the 11+ on physical performance in adolescent male football (soccer) players. Eighty-two 14- to 16-year-old male football players (11+ = 42 players, control = 40 players) participated. Teams were randomised to control (CON) and intervention (INT) groups. INT applied the 11+ injury prevention programme for 30 weeks at least twice a week as a warm-up. CON performed their standard warm-up. Motor performance tests were conducted 1 week prior and 1 week after the competition season. We used magnitude-based inferences and linear mixed-effects models to analyse performance test results. INT showed superior results compared to CON in the vertical jump height 7.5% (95%-CI 4.4%, 10.7%), the Bosco 15-s-jump test 7.2% (95%-CI 2.2%, 12.4%), and the Illinois agility test ?2.6% (95%-CI ?4.1%, ?1.1%). Possibly beneficial effects in favour of INT were found in the 9.1 m sprint test ?3.1% (95%-CI ?6.1%, 0.1%). Possibly harmful effects (i.e. in favour of CON) were observed in the dribbling test 2.8% (95%-CI ?0.8%, 6.4%). The 11+ warm-up programme can improve different performance measures in football players. Coaches might implement additional dribbling drills next to the 11+ to achieve improvements observed in dribbling ability when using a regular warm-up programme. 相似文献
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针对进口铁矿石压港现象十分严重这一情况,从武汉工业港矿石码头的实际出发,提出了对现有工艺流程改造,在堆场规模不变的情况下,提高码头的接卸能力,从而进一步提高武汉工业港码头竞争力。 相似文献
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[目的/意义]以学习敏锐度为切入点,探究图情人员在智慧服务这一陌生的新情境下,如何迅速提升自我素质和潜能从而更有效地胜任和完成新工作的相关问题,为未来更好地开展智慧服务提供参考和借鉴。[方法/过程]通过收集对国内"双一流"高校的189份调查问卷,运用结构方程的分析方法,深入研究智慧服务情境下图情服务人员的学习敏锐度,包括：①学习敏锐度测量的关键组成要素是否有效;②这些关键组成要素与服务创新意愿、服务成效之间的相关关系。[结果/结论]研究发现：智慧服务情境下,图情服务人员的学习敏锐度由自我洞察、人际敏锐、变革意愿和环境敏感四大关键因素组成,它们分别与服务创新意愿、服务成效呈现显著的正向相关关系;同时,服务创新意愿与服务成效之间呈现显著的正向相关关系。最后,针对图情服务的管理进行深入探讨,并提出相应对策建议。 相似文献