共查询到20条相似文献，搜索用时 203 毫秒
1.
通过高速摄影和文献资料法，对不同水平女子100米运动员的分析，发现高水平运动员起跨攻栏时的起跨距离、身体重心的水平速度明显优于水平相对低的运动员；腾空过栏时低水平运动员身体重心的垂直位移明显大于高水平运动员的值；下栏着地时着地点与身体重心垂直投影点的水平距离明显低于水平低的运动员的值。 相似文献
2.
薛川 《体育科技文献通报》2023,(7):101-102+157
本文以我国跨栏跑项目的一些优秀运动员为研究对象,采用视频分析和运动生物力学等方法,从起跨、攻栏和落地三个阶段对其技术特征进行描述和比较,结合二维运动学分析总结各个参数对跨栏技术的影响。结果表明：(1)在准备起跨攻栏时,着地与过栏后着地两个阶段的缓冲与蹬伸时间关系完全不同,起跨攻栏着地阶段,缓冲与蹬伸的时间比率为65%:35%,而着地阶段的缓冲与蹬伸时间比率为20%:80%。(2)腾空阶段,由于重心移动方向的改变,水平速度减小,垂直速度增大,跨栏运动员重心的水平速度会转换成垂直速度;过栏后,着地时间与着地缓冲时间应尽可能地缩短,以便在跨栏后减少重心水平速度的损失。(3)跨栏的效率也是由起跳攻栏角度、起跳和着地时脚与栏架距离的比例、腾空时间和跨栏的重心高度共同决定的。 相似文献
3.
主要采用高速摄影与运动录像解析法与实验法,对四川成都九名女子100米栏运动员8周的核心力量训练,通过训练前后对比分析研究发现：运动员身体素质与核心稳定能力水平有显著性提高,特别是髋关节灵活性及核心稳定性有非常显著性提高;运动员身体重心在栏上的运动轨迹有明显变化,主要表现为身体重心垂直投影点与栏的水平距离缩小,身体重心与栏的垂直距离变小,躯干前倾角变小,身体重心在垂直方向的位移变小;运动员对个人体能水平的控制能力有一定程度的提高,这主要表现在个人技术水平与现有体能水平的合理分配,也就是个人体能能力向技术水平提高的正迁移比例增加,起跨技术也有明显提高,着地技术虽有所改善但还有待于提高。 相似文献
4.
通过对我国部分优秀男子跳远运动员助跑最后三步离地距离、腾空距离及着地距离的研究,认为运动员助跑最后三步步长结构对助跑水平速度、身体重心高度以及起跳效果都有很大程度的影响;我国男子跳远运动员最后两步步长构成具有不合理性;倒数第二步着地距离过大,最后一步着地距离偏小。前者造成倒数第二步重心高度下降过多、最后一步减速严重、踏板瞬间身体重心水平速度偏低,后者造成起跳过程中垂直作功距离偏短、腾起垂直分速度及腾起角偏低。 相似文献
5.
一、跨栏步技术跨栏步即起跨腿的脚接触起跨点到过栏后摆动腿的脚接触地面时的一大步。它由起跨攻栏、腾空过栏、下栏着地构成。起跨攻栏时要获得一个较高的身体重心,起跨离地前身体重心前移,攻栏时要高摆摆动腿大腿,加大两腿夹角, 相似文献
6.
浅谈110米栏的直线性特征 总被引：2，自引：0，他引：2
一、身体重心轨迹的直线性要求 110米 (100米 )栏的理想状态是人体重心经过 110米 (110米 )的距离,而事实上,人的跑动不是一种平移,尤其是跨栏跑,过栏时不可避免地出现身体重心的上下起伏,其差值由栏间跑身体重心高度和过栏时身体重心高度决定,他们是跨栏跑直线性的关键。 正确的栏间跑技术应是重心高而平稳。优秀的跨栏运动员的栏间跑应象短跑运动员一样,身体重心上下起伏小,起跨过栏时身体重心在前后方向上的位移大,垂直方向上下波动小,这样,可以缩短腾空时间,达到经济实效的运动效果。 另外,在跨栏中,从起点到… 相似文献
7.
郭卫 《西安体育学院学报》1996,(4)
通过对优秀男子１１０ｍ栏运动员的前、后程的跨栏步的三个技术时相进行运动学技术对比分析。结果发现造成男子１１０ｍ栏运动员后程跨栏步减速主要是由后程起跨攻栏太近，重心水平速度损失明显，起跨攻栏支撑时间和下栏着地支撑时间太长，起跨腿在栏上时下压不积极等技术因素引起的。 相似文献
8.
十运会刘翔110米栏第五栏腾空过栏技术的运动学分析 总被引：1，自引：1，他引：0
采用一台日本产JVC9800小型数码摄像机对刘翔第五栏起跨攻栏技术分两次进行一维跟踪中速拍摄,采用平面数字量化、数据平滑处理和Sbcas2软件解析,与刘翔前两次比赛和前世界纪录保持者科林.杰克逊的技术参数对比。解析结果表明:刘翔腾空过栏阶段,稳定地加大了躯干的最大前倾角度、两腿最大夹角和过栏速度;起跨攻栏距离与下栏着地距离之比稳定在接近理论上的最理想比例;刘翔无论攻栏距离、下栏距离,还是跨栏步步长都是稳定的;刘翔十运会预赛和决赛的技术提高是:头、肩、臂和身体重心的上下升降幅度大大减小了,并且两次比较一致。 相似文献
9.
良好的跨栏步技术应体现出跨栏速度快,重心高,起跨角小,腾空后人体重心运动轨迹"平直"且接近栏顶,空中停留时问短、下栏快速支撑平稳,水平速度损失小,能顺利转入栏间跑。摆动腿在跨栏步技术中起着重要的作用。因此,跨栏步中摆动腿的技术必须符合上述跨栏技术规格的要求。一、起跨腿着地缓冲阶段摆动技术摆动腿等蹬离地面后即应充分折叠,快速前摆,使摆动腿重心尽快靠近身体重心垂线,以减小 相似文献
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11.
Gordon E. Barkwell 《Sports biomechanics / International Society of Biomechanics in Sports》2018,17(4):429-441
FINA recently approved the backstroke ledge (Omega OBL2) to improve backstroke start performance in competition, but its performance has not been thoroughly evaluated. The purpose of this study was to compare the mechanics of starts performed with and without the OBL2. Ten high-level backstroke swimmers performed three starts with, and three starts without, the OBL2. A wall-mounted force plate measured the lower limb horizontal impulse, vertical impulse, take-off velocity and take-off angle. Entry distance, time to 10 m and start of hip and knee extension were recorded using video cameras. Starts performed with the OBL2 had a 0.13 s lower time to 10 m, 2.5% less variability in time to 10 m and 0.14 m greater head entry distance. The OBL2 provides a performance advantage by allowing an increased head entry distance rather than larger horizontal impulse on the wall. This may be due to the swimmers assuming different body positions during the start manoeuvre. Additional studies are needed to evaluate factors that contribute to improved performance when using the OBL2. Swimmers should train with the OBL2 and use it in competition to ensure optimal start performance. 相似文献
12.
Takei Y Dunn JH Blucker E 《Sports biomechanics / International Society of Biomechanics in Sports》2003,2(2):141-162
The 16 highest-scored Roche vaults (G1) performed during the 2000 Olympic Games were compared with those receiving the 16 lowest-scores (G2). A 16-mm motion picture camera operating at 100 Hz recorded the vaults during the competition. The results of t tests (p < .05) indicated G1, compared to G2, had (a) shorter time of board support, greater normalised average upward vertical force and backward horizontal force exerted by the board, greater change in the vertical velocity while on the board, and greater vertical velocity at board take-off, (b) comparable linear and angular motions in pre-flight, (c) smaller backward horizontal impulse exerted by the horse, smaller loss of the horizontal velocity while on the horse, and greater horizontal and vertical velocities at horse take-off, (d) greater height and larger horizontal distance of post-flight, (e) higher body mass centre at knee release, and (f) higher mass centre, greater normalised moment of inertia, and smaller vertical velocity at mat touchdown. Therefore, gymnasts and coaches should focus on sprinting the approach; blocking and pushing-off the take-off board rapidly and vigorously; departing the board with a large vertical velocity; exerting large downward vertical force and small forward horizontal force from the hand-stand position while on the horse; departing the horse with large horizontal and vertical velocities; and completing the majority of the double salto forward near the peak of trajectory and releasing the knees above the top of the horse to prepare for a controlled landing. 相似文献
13.
对我国部分优秀男子跳高运动员起跳技术的运动学分析 总被引：18，自引：1，他引：17
通过三维摄影，对我国部分男子跳高运动员的起跳技术进行了分析。结果表明，我国运动员与世界优秀运动员在起跳技术方面存在着较大的差异，主要表现为前者在助跑与起跳衔接阶段的质心水平速度较低，倒1步身体内倾角度变化呈大—小趋势；在起跳阶段，起跳腿着地时的质心水平速度低，身体质心垂直加速距离较短以及起跳腿缓冲蹬伸时间比例不完全符合力学原理等。另外，我国运动员在起跳过程中普遍存在着起跳腿蹬伸不充分以及摆动腿摆速和摆幅偏小的问题。 相似文献
14.
运用影片拍摄及解析的方法对成绩在 6.30 m以上的 6名中国优秀女子运动员摆动腿在助跑最后一步和起跳过程中的运动学特征进行分析。研究表明,在助跑最后一步蹬伸阶段优秀女跳远运动员摆动腿髋的水平速度与水平速度增加值呈高度正相关;着板时,摆动腿摆动角速度与起跳脚水平速度呈高度负相关;起跳过程的缓冲阶段中,摆动腿的摆动使身体重心高度呈上升趋势,同时垂直速度持续升高,占腾起垂直分速度值的53.1％。 相似文献
15.
《European Journal of Sport Science》2013,13(8):687-695
AbstractThe objective of this study was to determine the relationship between different variables measured with a force plate during the swimming start push-off phase and start performance presented by times to 5, 10 and 15?m. Twenty-one women from the Slovenian national swimming team performed two different swim starts (freestyle and undulatory) on a portable force plate to a distance further than 15?m. Correlations between push-off variables and times to 5, 10 and 15?m were quantified through Pearson's product-moment correlation coefficient (r). The variables that significantly correlated (p?<?.05) to all times measured in the two starts performed were: average horizontal acceleration (freestyle: r?=??0.58 to ?0.71; and undulatory: r?=??0.55 to ?0.66), horizontal take-off velocity (freestyle: r?=??0.56 to ?0.69; and undulatory: r?=??0.53 to ?0.67) and resultant take-off velocity (freestyle: r?=??0.53 to ?0.65; and undulatory: r?=??0.52 to ?0.61). None of the variables derived from the vertical force were correlated to swimming start performance (p?>?.05). Based on the results of this study, we can conclude that horizontal take-off velocity and average horizontal acceleration (calculated as the average horizontal force divided by swimmer's body mass) are the variables most related to swimming start performance in experienced swimmers, and therefore could be the preferred measures to monitor swimmers’ efficiency during the push-off phase. 相似文献
16.
The swimming start is typically broken into three sub-phases; on-block, flight, and underwater phases. While overall start performance is highly important to elite swimming, the contribution of each phase and important technical components within each phase, particularly with the new kick-start technique, has not been established. The aim of this study was to identify technical factors associated with overall start performance, with a particular focus on the underwater phase. A number of parameters were calculated from 52 starts performed by elite freestyle and butterfly swimmers. These parameters were split into above-water and underwater groupings, before factor analysis was used to reduce parameter numbers for multiple regression. For the above-water phases, 81% of variance in start performance was accounted for by take-off horizontal velocity. For the underwater water phase, 96% of variance was accounted for with time underwater in descent, time underwater in ascent and time to 10 m. Therefore, developing greater take-off horizontal velocity and focussing on the underwater phase by finding the ideal trajectory will lead to improved start performance. 相似文献
17.
Karla de Jesus Kelly de Jesus J. Arturo Abraldes Alexandre Igor Araripe Medeiros Ricardo J. Fernandes João Paulo Vilas-Boas 《Journal of sports sciences》2016,34(9):871-877
We aimed to analyse the handgrip positioning and the wedge effects on the backstroke start performance and technique. Ten swimmers completed randomly eight 15 m backstroke starts (four with hands on highest horizontal and four on vertical handgrip) performed with and without wedge. One surface and one underwater camera recorded kinematic data. Standardised mean difference (SMD) and 95% confidence intervals (CI) were used. Handgrip positioning did not affect kinematics with and without wedge use. Handgrips horizontally positioned and feet over wedge displayed greater knee angular velocity than without it (SMD = ?0.82; 95% CI: ?1.56, ?0.08). Hands vertically positioned and feet over wedge presented greater take-off angle (SMD = ?0.81; 95% CI: ?1.55, ?0.07), centre of mass (CM) vertical positioning at first water contact (SMD = ?0.97; 95% CI: ?1.87, ?0.07) and CM vertical velocity at CM immersion (SMD = 1.03; 95% CI: 0.08, 1.98) when comparing without wedge use. Swimmers extended the hip previous to the knee and ankle joints, except for the variant with hands vertically positioned without wedge (SMD = 0.75; 95% CI: ?0.03, 1.53). Swimmers should preserve biomechanical advantages achieved during flight with variant with hands vertically positioned and wedge throughout entry and underwater phase. 相似文献
18.
Bradshaw EJ Le Rossignol P 《Sports biomechanics / International Society of Biomechanics in Sports》2004,3(2):249-262
The aim of this study was to identify the anthropometric and physical prerequisites for high difficulty floor tumbling and vaulting. Twenty 8-14 year old female talent-selected gymnasts performed handstand push-offs, and single and multiple jumps on a portable Kistler force plate. The force curves were analysed using Kistler and Excel software to obtain peak displacement, peak take-off force, and power The gymnasts were also assessed for sprinting, with and without vaulting, and standing broad jump performances. Video footage from the vault take-off was analysed using Video Expert II software to obtain the horizontal and vertical take-off velocities. Each gymnast's best vault starting score, three best floor tumbling skills, and anthropometric characteristics were recorded. Statistical analysis included one-way analysis of variance (ANOVA) to examine the effect of age (8-10 years, 11-12 years, 13-14 years) on the performance measures and linear regression analysis with performance start score for vault or best floor tumbling score as the outcome variable. The best regression model for indicating vaulting talent had, as predictor variables, resultant velocity at take-off from the board, squat jump power, and average power during the last five jumps in the continuous bent-leg jump series. The best regression model for indicating floor tumbling ability had, as predictor variables, age, vault running velocity, and reduced ground contact time in a handstand push-off. 相似文献
19.
The start kinematics has been reported to differ between male and female sprinters. This study aimed to determine whether kinematic differences between the sexes are attributable to an effect of sex per se, or rather to the absolute performance level of the sprinters, quantified by the 100-m time. A total of 20 sprinters (10 M, 10 F), including world-class and elite athletes, were assessed. Start phases from the “set” position to the first two steps were analysed. Linear regression analyses showed a few significant differences between sexes when taking into account the effect of performance level: M had shorter pushing phase duration, higher horizontal velocity at block clearing, and shorter contact times of the first two steps. Conversely, the performance level affected most of the examined parameters: faster sprinters showed the centre of mass (CM) closer to the ground and a more flexed front knee in the “set” position, longer pushing phase duration, lower vertical velocity of the CM at block clearing, and longer contact times and shorter flight times in the first two steps. These findings suggest that the start kinematics is only partially affected by the sex of sprinters, whereas a bigger role is played by their performance level. 相似文献
20.
Yusuke Ikeda Hiroshi Ichikawa Rio Nara Yasuhiro Baba Yoshimitsu Shimoyama 《Journal of sports sciences》2017,35(2):189-195
The purpose of this study was to determine the installation of the backstroke start device reduces 15-m time. Thirteen college swimmers participated in this study. The aerial start and underwater motions were recorded with two digital video cameras. The center of mass (CM) of the swimmer, angular displacements and velocities of the shoulder, hip and knee joints were calculated. As an indicator of performance, the 5- and 15-m times were measured. The 5- and 15-m times in the backstroke start device condition were significantly shorter than in the non-backstroke start device condition. The vertical velocities of the CM at hand-off and toe-off in the backstroke start device condition were significantly greater than in the non-backstroke start device condition, while there was no significant difference in the CM horizontal velocity at toe-off. As a result, the height of the great trochanter at entry of the fingertips, with the backstroke start device, was 15 cm higher than in the non-backstroke start device condition. In addition, the CM horizontal velocities at 5 m in the backstroke start device condition were significantly greater than those of the non-backstroke start device. Thus, the use of the backstroke start device may reduce the 15-m time by diminution of the entry area. 相似文献