共查询到19条相似文献，搜索用时 162 毫秒
1.
着重从人体多环节链的相对运动来分析撒手时人体质心运动和翻转角动量的大小 ,并推导出了理论计算公式。研究认为 ,人体质心运动与翻转角动量大小由各环节之间复杂的相对运动关系所决定 ,随着人体运动环节数目的增加 ,分析这些环节的相对运动对人体质心运动和角动量的协同作用效果 ,将变得十分复杂。 相似文献
2.
体质的概念及其与健康的关系 总被引：27，自引：0，他引：27
对体育理论中的体质定义进行研究。主要结论：体质即人体的质量，是人体在先天遗传的基础上和后天环境的影响下，在生长、发育和衰老的过程中逐渐形成的身、心两方面相对稳定的特质。体质与健康的关系：(1)体质是健康的物质基础，健康是体质的外在表现。二者是紧密联系、不可分割的。(2)体质是一种特质，健康是一种状态。(3)体质是人体维持良好健康状态的能力。 相似文献
3.
运动员体能训练的新思路———核心稳定性训练 总被引：7，自引：1，他引：6
良好的动态稳定能力是运动员竞技能力发挥的基础,国外优秀运动员进行身体稳定性训练取得了明显的效果,而目前我国运动员体能训练理论和方法中却缺少了对身体稳定能力的研究,在借鉴国外研究的基础上,提出核心稳定性的定义,并从解剖学和生理学角度分析核心稳定性训练的机制和特点.研究认为,人体"核心"的解剖学位置是身体膈肌以下至盆底肌之间的区域,核心稳定性是指人体通过核心肌群的收缩保持或维持脊柱和骨盆在正常解剖学位置的能力;核心稳定性训练即是动态的核心稳定肌的本体感受性训练,又是核心运动肌的力量训练,它摒弃了现有力量训练方法存在的弊端,有着与传统体能训练不可比拟的优势,为我国运动员体能训练提供新思路. 相似文献
4.
自由式滑雪空中技巧运动员落地稳定性主要影响因素的研究 总被引：2，自引：1，他引：1
对自由式滑雪空中技巧运动员落地稳定性问题建立了四个运动环节的人体运动模型。雪板雪靴、足、小腿定义为环节1,大腿定义为环节2,躯干、头定义为环节3,上臂、前臂、手定义为环节4。根据平动动坐标系下相对动量矩定理建立了描述自由式滑雪空中技巧运动员落地稳定性控制人体对人体质心动量矩的模型。模型是有效的,并能反应落地稳定性控制的内在主要影响因素。 相似文献
5.
《体育科技文献通报》2002,(6)
G804 20022519体质的概念及其与健康的关系[刊,中,I]/何仲恺//体育科学.-2002.-22(2).-37-38参3(LF)体质//概念//健康//关系对体育理论中的体质定义进行研究。主要结论:体质即人体的质量,是人体在先天遗传的基础上和后天环境的影响下,在生长、发育和衰老的过程中逐渐形成的身、心两方面相对稳定的特质。体质与健康的关系:(1)体质是健康的物质基础,健康是体质的外在表现。两者是紧密联系、不可分割的。(2)体质是一种特质,健康是一种状态。(3)体质是人体维持良好健康状态的能力。 相似文献
6.
足球运动员在运动中完成技术动作的质量和效果，受到自身身体稳度的影响。保持身体平衡和有意识冲破平衡都是为了达到高质量完成技术动作和有效战术目的。本文着重从理论上探讨人体重心与稳度关系变化对足球技术的影响。 相似文献
7.
跑是一个典型的连续的周期性动作。一个单步由支撑和腾空两个阶段构成,两个单步组成的一个复步构成一个完整的周期动作。在跑的支撑阶段,通过支撑足与地面相互作用,能使人体获得向前位移;腾空阶段,人体循惯性向前运动。跑的支撑阶段,由三维测力台所测支撑反作用力在三维空间的三个平面内投影的矢量端图,可看出其大小,方向和性质。它对人体作用的形式是复杂的,是一个不断变化的、在大部分时间内作用线不通过人体质心的力。这是由于人体结构特点、支撑阶段人体重心与支点 相似文献
8.
人体运动链功能发挥的同步性和高效性对运动员运动技术的发挥有着重要影响.为了验证沙滩排球运动员核心稳定性与其最大扣球速度之间的关系,即与人体运动链功能之间的关系,通过核心稳定性系列测试以及雷达测速枪分别对我国高水平沙滩排球运动员核心稳定性和最大扣球速度进行评价和相关性分析,结果表明,高水平沙滩排球运动员最大扣球速度与作为核心稳定性组成部分的水平面核心回旋肌群爆发力有显著的相关性,与其他两个运动面的核心肌群耐力相关性非常小和没有相关关系.建议沙滩排球运动员提高排球扣球速度的练习应侧重水平面核心回旋肌群的爆发力训练. 相似文献
9.
一、“手倒立”动作要领与学练步骤
1．动作要领
人体在倒立时，身体重心的投影点在地面上的两手之间，重心投影点距支撑面中心越近，稳度越大；平衡技术的好坏，主要表现在对身体重心在水平方位的控制调节上。 相似文献
10.
对自由式滑雪空中技巧落地稳定性的实验研究 总被引：5，自引：2，他引：3
本文对自由式滑雪空中技巧落地稳定性做了实验研究和理论分析。研究结果表明,落地稳定性的成功因素与着陆时的人体剩余动量矩、躯干倾角、着陆时足的加速度、屈膝屈髋速度等因素有关。其中以人体剩余动量矩、躯干倾角引起的克服剩余动量矩的重力矩为最大影响因素,屈膝屈髋速度为重要影响因素,快速的下蹲动作能有效地克服剩余人体动量矩。实测落地成功运动员的着陆人体运动学参数表明,躯干倾角比着陆坡面的垂线倾角小30°左右时落地成功;着陆后处于失稳边缘的运动员使用快速下蹲技术,能使运动员转危为安。 相似文献
11.
Golf requires proper dynamic balance to accurately control the club head through a harmonious coordination of each human segment and joint. In this study, we evaluated the ability for dynamic balance during a golf swing by using the centre of mass (COM)–centre of pressure (COP) inclination variables. Twelve professional, 13 amateur and 10 novice golfers participated in this study. Six infrared cameras, two force platforms and SB-Clinic software were used to measure the net COM and COP trajectories. In order to evaluate dynamic balance ability, the COM–COP inclination angle, COM–COP inclination angular velocity and normalised COM–COP inclination angular jerk were used. Professional golfer group revealed a smaller COM–COP inclination angle and angular velocity than novice golfer group in the lead/trail direction (P < 0.01). In the normalised COM–COP inclination angular jerk, the professional golfer group showed a lower value than the other two groups in all directions. Professional golfers tend to exhibit improved dynamic balance, and this can be attributed to the neuromusculoskeletal system that maintains balance with proper postural control. This study has the potential to allow for an evaluation of the dynamic balance mechanism and will provide useful basic information for swing training and prevention of golf injuries. 相似文献
12.
文章旨在计算下肢环节惯性参数对逆向动力学计算结果的敏感性.以中国人体环节惯性参数模型为基础,人为地改变下肢环节惯性参数值的范围（±5％和±10％）,结合运动学和动力学数据,分别进行逆向动力学计算.结果表明,大腿环节质心位置改变10％对髋关节力矩最大值的影响程度达到-0.49％到0.63％,对应力矩最小值的变化为-24.3％和18.47％;小腿环节质心位置改变10％对膝关节力矩和做功影响均接近0.4％,对较远的髋关节作用影响更弱;无论是大腿还是小腿,环节质量的敏感性要高于环节相对质心位置（P＜0.05）.下肢惯性参数改变对逆向动力学计算结果的影响不可忽略,环节惯性参数对动力链较近关节影响最大,环节质量参数的敏感度显著高于环节相对质心位置参数的敏感度. 相似文献
13.
This study aimed to investigate specific muscle synergies in elite ice hockey players indicating highly developed postural control strategies used to restore balance against unexpected external perturbations. Seven elite athletes (EA) on the women’s national ice hockey team and 7 non-athletes (NA) participated in this study. Based on trajectories of centre of mass (COM), analysis periods were divided into an initial phase (a balance disturbance after perturbation onset) and a reversal phase (a balance recovery response), respectively. Muscle synergies were extracted at each phase by using non-negative matrix factorization. k-means cluster analysis was performed to arrange similar muscle synergies in all participants. EA showed significantly shorter recovery period of COM and smaller body sway than NA. In the initial phase, we identified 2 EA-specific synergies related to ankle plantar flexors or neck extensors. In the case of an NA-specific synergy, co-activation of the ankle plantar flexors and dorsiflexors was found. In the reversal phase, no specific muscle synergies were identified. As the results, EA-specific muscle synergies showed low co-activation strategy of agonists and antagonists in ankle and neck extensors. Our results could provide critical information for rehabilitation strategies in athletes requiring high postural stability. 相似文献
14.
Taylour J. Hinshaw Daniel J. Davis Jacob S. Layer Margaret A. Wilson Qin Zhu 《Journal of sports sciences》2019,37(4):414-423
Increased lateral trunk bending to the injured side has been observed when ACL injuries occur. The purpose was to quantify the effect of mid-flight lateral trunk bending on center of mass (COM) positions and subsequent landing mechanics during a jump-landing task. Forty-one recreational athletes performed a jump-landing task with or without mid-flight lateral trunk bending. When the left and right trunk bending conditions were compared with the no trunk bending condition, participants moved the COM of the upper body to the bending direction, while the COM of the pelvis, ipsilateral leg, and contralateral leg moved away from the bending direction relative to the whole body COM. Participants demonstrated increased peak vertical ground reaction forces (VGRF) and knee valgus and internal rotation angles at peak VGRF for the ipsilateral leg, but decreased peak VGRF and knee internal rotation angles at peak VGRF and increased knee varus angles at peak VGRF for the contralateral leg. Mid-flight lateral trunk resulted in an asymmetric landing pattern associated with increased ACL loading for the ipsilateral leg. The findings may help to understand altered trunk motion during ACL injury events and the discrepancy in ACL injuries related to limb dominance in badminton and volleyball. 相似文献
15.
Sofie Debaere Christophe Delecluse Dirk Aerenhouts Friso Hagman 《Journal of sports sciences》2015,33(19):2016-2024
The aim of this study was to relate the contribution of lower limb joint moments and individual muscle forces to the body centre of mass (COM) vertical and horizontal acceleration during the initial two steps of sprint running. Start performance of seven well-trained sprinters was recorded using an optoelectronic motion analysis system and two force plates. Participant-specific torque-driven and muscle-driven simulations were conducted in OpenSim to quantify, respectively, the contributions of the individual joints and muscles to body propulsion and lift. The ankle is the major contributor to both actions during the first two stances, with an even larger contribution in the second compared to the first stance. Biarticular gastrocnemius is the main muscle contributor to propulsion in the second stance. The contribution of the hip and knee depends highly on the position of the athlete: During the first stance, where the athlete runs in a forward bending position, the knee contributes primarily to body lift and the hip contributes to propulsion and body lift. In conclusion, a small increase in ankle power generation seems to affect the body COM acceleration, whereas increases in hip and knee power generation tend to affect acceleration less. 相似文献
16.
Caroline Göpfert Mikko V. Pohjola Vesa Linnamo Olli Ohtonen Walter Rapp Stefan J. Lindinger 《Sports Engineering》2017,20(2):141-153
The purpose of this paper was to present and evaluate a methodology to determine the contribution of bilateral leg and pole thrusts to forward acceleration of the centre of mass (COM) of cross-country skiers from multi-dimensional ground reaction forces and motion capture data. Nine highly skilled cross-country (XC) skiers performed leg skating and V2-alternate skating (V2A) under constant environmental conditions on snow, while ground reaction forces measured from ski bindings and poles and 3D motion with high-speed cameras were captured. COM acceleration determined from 3D motion analyses served as a reference and was compared to the results of the proposed methodology. The obtained values did not differ during the leg skating push-off, and force–time curves showed high similarity, with similarity coefficients (SC) >0.90 in the push-off and gliding phases. In V2A, leg and pole thrusts were shown to contribute 35.1 and 65.9% to the acceleration of the body, respectively. COM acceleration derived from ground reaction forces alone without considering the COM position overestimated the acceleration compared to data from motion analyses, with a mean difference of 17% (P < 0.05) during leg push-off, although the shapes of force–time curves were similar (SC = 0.93). The proposed methodology was shown to be appropriate for determining the acceleration of XC skiers during leg skating push-off from multi-dimensional ground reaction forces and the COM position. It was demonstrated that both the COM position and ground reaction forces are needed to find the source of acceleration. 相似文献
17.
The aim of this study was to advance current movement analysis methodology to enable a technique analysis in sports facilitating (1) concurrent comparison of the techniques between several athletes; (2) identification of potentially beneficial technique modifications and (3) a visual representation of the findings for feedback to the athletes. Six elite cross-country skiers, three world cup winners and three national elite, roller ski skated using the V2 technique on a treadmill while their movement patterns were recorded using 41 reflective markers. A principal component analysis performed on the marker positions resulted in multi-segmental “principal” movement components (PMs). A novel normalisation facilitated comparability of the PMs between athletes. Additionally, centre of mass (COM) trajectories were modelled. We found correlations between the athletes’ performance levels (judged from race points) and specific features in the PMs and in the COM trajectories. Plausible links between COM trajectories and PMs were observed, suggesting that better performing skiers exhibited a different, possibly more efficient use of their body mass for propulsion. The analysis presented in the current study revealed specific technique features that appeared to relate to the skiers’ performance levels. How changing these features would affect an individual athlete’s technique was visualised with animated stick figures. 相似文献
18.
Qipeng Song Shen Wang Del P. Wong Jingyi Zhou Wei Sun Cui Zhang 《Sports biomechanics / International Society of Biomechanics in Sports》2018,17(3):402-413
The effects of long-term Tai Chi exercise on body stability of the elderly during stair ascent under high and low illumination were investigated. Forty-five healthy elderly women were divided into three groups, namely, Tai Chi exercise group, brisk walking group and no-exercise control group. All the participants ascended a staircase, during which force platforms and a motion capture system collected the data. Under the high illumination, Tai Chi exercise participants exhibited higher loading rate and anteroposterior centre of pressure (COPap) displacement as well as a lower braking impulse than no-exercise group. Under the low illumination, Tai Chi exercise participants demonstrated higher COPap and mediolateral centre of pressure (COPml) displacements as well as lower braking and lateral impulses compared with no-exercise participants. The centre of mass (COM)ml sway in Tai Chi and no exercise participants were higher, the loading rates in Tai Chi and walking participants were higher, and the lateral impulse in no exercise participants was higher under low illumination than under high illumination. Thus, low illumination increases the risk of falling. Tai Chi participants increased their foot clearance, head inclination angle and COPap displacement under low illumination to increase their stability during stair ascent. 相似文献
19.
核心力量训练的实质及在我国竞技体育的实践 总被引：3，自引：0，他引：3
核心力量是一种稳定人体核心部位、控制重心运动、传递上下肢力量为主要目的的力量能力,是人体运动的一个"发力源".核心力量训练的实质就是人体核心稳定性.核心力量训练在21世纪初才传入我国竞技体育实践中,可分为两个时期:初期大多数人没有真正了解核心力量训练的实质,体能和运动成绩提高不显著;自2006年后核心力量训练在我国已呈现方兴未艾之势,虽然在方法、手段、效果评价等方面还不够完善,但在整体上是比较成功的.目前国家和省市的运动队都引进了核心力量训练. 相似文献