共查询到20条相似文献，搜索用时 250 毫秒
1.
《体育科技文献通报》1999,(3)
G822.03,G804.63 9901255对跑动力争鸣的剖析=Analyzing the contention ofthe running motive force〔刊,中,I〕/谢永文,胡耿丹//中国体育科技.-1999.-35(1).-41-43参9(BJ)跑//蹬伸动作//作用力对有关跑的动作不是蹬地反用力的种种新观点进行了剖析,本文赞同跑“动力是蹬地反用力”这一传统理论,而各种新观点仅仅是对跑动时运动器官和肌肉活动的表象描述,其错误根源在于混淆了内力和外力的内涵、作用效果和互相转化关系。 相似文献
2.
陈有源 《武汉体育学院学报》1988,(4)
近几年来,许多研究者发现,优秀短跑选手的蹬地动作可以很不充分,刘易斯足离地时的腾角仅为143°。笔者研究证明后蹬反作用力不能成为跑的唯一或主要动力。L.Wastr提出了决定跑速的因素不是快速蹬地而是有力伸髋的新观点。朱谦则认为跑的技术不是蹬地而是趴地,提出了把后蹬改为后趴的短跑新技术。这些研究结果至少对跑的蹬地技术提出了质疑。因此,研究短跑途中跑腿运动的正确技术究竟是什么?对跑的技术教学和训练具有非常重要的意义。 相似文献
3.
对几种现代短跑技术专门练习的分析 总被引：2，自引：0，他引：2
一、引言传统短跑理论强调“后蹬是人体前进的动力阶段”，“后蹬力量越大，产生的加速度越大，速度越快，跑时要加大蹬地力量”。这种认识忽视了高速跑动过程中，人体各运动环节用力的共济性和系统性，缺乏对跑动中摆动腿摆动动作主导作用的深刻认识。有人把现代短跑摆动式着地技术看成是“屈蹬式”蹬伸技术，这种观点忽视了跑动动作协调配合的整体效益。我国学者王保成（１９９５年）提出，现代短跑运动和短跑技术的本质特征是以髋为轴的高速摆动——平动运动，髋关节运动是人体水平加速的关键环节。这种观点与国外大量有关研究资料相一致… 相似文献
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短跑动力的研究 总被引：1，自引：0，他引：1
陈有源 《武汉体育学院学报》1985,(1)
在跑的理论和训练中,一直认为后蹬反作用力是短跑的唯一或主要动力,本文提出与此相反的看法,认为足与地面相互作用产生的摩擦力(外力)使足固定,支撑腿肌肉收缩产生的力矩(内力)是跑的主要动力。人体因支撑转动而产生的蹬地反作用力的主要作用是增加腾空步长,对足离地时的跑速增加很小,不能成为短跑的主要动力。短跑的动力究竞是什么?我们期待专家和读者参加讨论。 相似文献
6.
从表面上看,我国关于短跑途中技术原理之争是蹬摆之争,实际上是看问题的方法和角度不别,片面地将跑的动力视为某一动作环节所致。因而对跑的整体要求缺乏准确的把握。短跑的基本特征,要求是快的动作速度,因而对跑的各个段落、动作、环节都要求快。短跑节奏与供能和放松能力有关,而不是人为的主动调整。 相似文献
7.
论人体运动的动力来源 总被引：2，自引：0，他引：2
该文对人体运动的动力来源提出了新的理论,即“人体的任何肢体和身体总重心能够主动发生各种位移运动的动力,只能是人体的相应肌肉在肢体的末端环节不固定和固定于地面与其它物体条件下发生收缩产生的力矩。人体走、跑、跳的动力只能或主要是支撑腿或起跳腿的相应肌肉在足固定于地面条件下发生收缩产生动力矩”。否定了“人体走、跑、跳的动力是蹬地或动支撑反作用力”的传统观念。在此发表,以期引起行家的争鸣。 相似文献
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就短跑途中跑动力来源的各种观点加以对比分析，认为后蹬不是短跑途中跑的唯一动力来源，对途中跑中动力的各种来源不能片面讨论，应辨证地来看待与分析。 相似文献
10.
在中学体育课后蹬跑的教学中，如果没有明确的教学目标，没有很好的教学方法，学生学习就没有兴趣和动力，后蹬跑练习的质量和效果就不好，不容易体会进行间的后蹬跑动作。我在教后蹬跑练习时，采用“三层目标”教学法，让学生有目标地体会后蹬跑身体动作，具体方法如下。 相似文献
11.
Romanov N Fletcher G 《Sports biomechanics / International Society of Biomechanics in Sports》2007,6(3):434-452
The relationship between the affect and timing of the four forces involved in running (gravity, ground reaction force, muscle force, and potential strain energy) is presented. These forces only increase horizontal acceleration of the centre of mass during stance but not flight. The current hierarchical models of running are critiqued because they do not show gravity, a constant force, in affect during stance. A new gravitational model of running is developed, which shows gravity as the motive force. Gravity is shown to cause a torque as the runner's centre of mass moves forward of the support foot. Ground reaction force is not a motive force but operates according to Newton's third law; therefore, the ground can only propel a runner forward in combination with muscle activity. However, leg and hip extensor muscles have consistently proven to be silent during leg extension (mid-terminal stance). Instead, high muscle-tendon forces at terminal stance suggest elastic recoil regains most of the centre of mass's height. Therefore, the only external motive force from mid-terminal stance is gravity via a gravitational torque, which causes a horizontal displacement. The aim of this paper is to establish a definitive biomechanical technique (Pose method) that is easily taught to runners (Romanov, 2002): falling forwards via a gravitational torque while pulling the support foot rapidly from the ground using the hamstring muscles. 相似文献
12.
Nicholas Romanov 《Sports biomechanics / International Society of Biomechanics in Sports》2013,12(3):434-452
The relationship between the affect and timing of the four forces involved in running (gravity, ground reaction force, muscle force, and potential strain energy) is presented. These forces only increase horizontal acceleration of the centre of mass during stance but not flight. The current hierarchical models of running are critiqued because they do not show gravity, a constant force, in affect during stance. A new gravitational model of running is developed, which shows gravity as the motive force. Gravity is shown to cause a torque as the runner's centre of mass moves forward of the support foot. Ground reaction force is not a motive force but operates according to Newton's third law; therefore, the ground can only propel a runner forward in combination with muscle activity. However, leg and hip extensor muscles have consistently proven to be silent during leg extension (mid-terminal stance). Instead, high muscle–tendon forces at terminal stance suggest elastic recoil regains most of the centre of mass's height. Therefore, the only external motive force from mid-terminal stance is gravity via a gravitational torque, which causes a horizontal displacement. The aim of this paper is to establish a definitive biomechanical technique (Pose® method) that is easily taught to runners (Romanov, 2002): falling forwards via a gravitational torque while pulling the support foot rapidly from the ground using the hamstring muscles. 相似文献
13.
Nilsson J Jakobsen V Tveit P Eikrehagen O 《Sports biomechanics / International Society of Biomechanics in Sports》2003,2(2):227-236
The purpose of the investigation was to study the relationship between thrust phase duration, ground reaction force, velocity increase after pole thrust and pole angles versus pole length during double poling in roller skiing. Seven male regional elite cross-country skiers volunteered as subjects for the study. The subjects performed a maximal double pole thrust on roller skis with each of the three different pole lengths: 'short', self-selected (normal) and 'long'. The short and long poles were 7.5 cm shorter and 7.5 cm longer than the self-selected pole length. The subjects made seven maximal pole thrusts with each pole length, which were randomly selected during 21 trials. For each trial the subjects accelerated from a 1.2 m high downhill slope attaining a speed of 3.92 m.s-1 before making a maximal double pole thrust on a force plate placed at the bottom of the slope. The vertical (F2), anterior-posterior (Fy) and mediolateral (Fx) reaction forces of the left pole were measured by the force plate. The positions of the pole were recorded in 3-D by an opto-electronic system. Thrust phase duration, impulse, mean force, velocity increase after pole thrust and pole angles were calculated from the recorded data. Double poling with long poles produced a significantly larger propulsive anterior-posterior reaction force impulse and velocity increase than normal (p < .05) and short poles (p < .05). This was in spite of a larger mean anterior-posterior reaction force being produced with short poles. Thus, thrust phase duration was a primary factor in determining propulsive anterior-posterior impulse. For the practitioner, the results can be useful in the selection of pole length when the aim is to increase thrust phase duration, anterior-posterior force impulse and velocity. 相似文献
14.
The purpose of this study was to investigate the interaction of foot strike and common speeds on sagittal plane ankle and knee joint kinetics in competitive rear foot strike (RFS) runners when running with a RFS pattern and an imposed forefoot strike (FFS) pattern. Sixteen competitive habitual male RFS runners ran at two different speeds (i.e. 8 and 6?min?mile?1) using their habitual RFS and an imposed FFS pattern. A repeated measures analysis of variance was used to assess a potential interaction between strike pattern and speed for selected ground reaction force (GRF) variables and, sagittal plane ankle and knee kinematic and kinetic variables. No foot strike and speed interaction was observed for any of the kinetic variables. Habitual RFS yielded a greater loading rate of the vertical GRF, peak ankle dorsiflexor moment, peak knee extensor moment, peak knee eccentric extensor power, peak dorsiflexion and sagittal plane knee range of motion compared to imposed FFS. Imposed FFS yielded greater maximum vertical GRF, peak ankle plantarflexor moment, peak ankle eccentric plantarflexor power and sagittal plane ankle ROM compared to habitual RFS. Consistent with previous literature, imposed FFS in habitual RFS reduces eccentric knee extensor and ankle dorsiflexor involvement but produce greater eccentric ankle plantarflexor action compared to RFS. These acute differences between strike patterns were independent of running speeds equivalent to typical easy and hard training runs in competitive male runners. Current findings along with previous literature suggest differences in lower extremity kinetics between habitual RFS and imposed FFS running are consistent among a variety of runner populations. 相似文献
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文章运用文献资料法、逻辑分析法,从时代发展的需要、武术功能的延续、国际化进程和奥运战略四个方面分析了竞技武术在当代繁荣发展的动力。指出竞技武术是新时期武术发展的需要,同时竞技武术的繁荣发展也是武术国际化和我国奥运战略的强大动力,是新时期武术发展的里程碑。 相似文献
16.
We have previously argued that there may actually be no significant eccentric, but rather predominantly an isometric action of the hamstring muscle fibres during the swing phase of high-speed running when the attachment points of the hamstrings are moving apart. Based on this we suggested that isometric rather than eccentric exercises are a more specific way of conditioning the hamstrings for high-speed running. In this review we argue that some of the presumed beneficial adaptations following eccentric training may actually not be related to the eccentric muscle fibre action, but to other factors such as exercise intensity. Furthermore, we discuss several disadvantages associated with commonly used eccentric hamstring exercises. Subsequently, we argue that high-intensity isometric exercises in which the series elastic element stretches and recoils may be equally or even more effective at conditioning the hamstrings for high-speed running, since they also avoid some of the negative side effects associated with eccentric training. We provide several criteria that exercises should fulfil to effectively condition the hamstrings for high-speed running. Adherence to these criteria will guarantee specificity with regards to hamstrings functioning during running. Practical examples of isometric exercises that likely meet several criteria are provided. 相似文献
17.
Johnny Nilsson Vidar Jakobsen Per Tveit Olav Eikrehagen 《Sports biomechanics / International Society of Biomechanics in Sports》2013,12(2):227-236
The purpose of the investigation was to study the relationship between thrust phase duration, ground reaction force, velocity increase after pole thrust and pole angles versus pole length during double poling in roller skiing. Seven male regional elite cross‐country skiers volunteered as subjects for the study. The subjects performed a maximal double pole thrust on roller skis with each of the three different pole lengths: ‘short’, self‐selected (normal) and ‘long’. The short and long poles were 7.5 cm shorter and 7.5 cm longer than the self‐selected pole length. The subjects made seven maximal pole thrusts with each pole length, which were randomly selected during 21 trials. For each trial the subjects accelerated from a 1.2 m high downhill slope attaining a speed of 3.92 m.s‐1 before making a maximal double pole thrust on a force plate placed at the bottom of the slope. The vertical (Fz), anterior‐posterior (Fy) and medio‐lateral (Fx) reaction forces of the left pole were measured by the force plate. The positions of the pole were recorded in 3‐D by an opto‐electronic system. Thrust phase duration, impulse, mean force, velocity increase after pole thrust and pole angles were calculated from the recorded data. Double poling with long poles produced a significantly larger propulsive anterior‐posterior reaction force impulse and velocity increase than normal (p < .05) and short poles (p < .05). This was in spite of a larger mean anterior‐posterior reaction force being produced with short poles. Thus, thrust phase duration was a primary factor in determining propulsive anterior‐posterior impulse. For the practitioner, the results can be useful in the selection of pole length when the aim is to increase thrust phase duration, anterior‐posterior force impulse and velocity. 相似文献
18.
It is widely assumed that there is an eccentric hamstring muscle fibre action during the swing phase of high-speed running. However, animal and modelling studies in humans show that the increasing distance between musculotendinous attachment points during forward swing is primarily due to passive lengthening associated with the take-up of muscle slack. Later in the swing phase, the contractile element (CE) maintains a near isometric action while the series elastic (tendinous) element first stretches as the knee extends, and then recoils causing the swing leg to forcefully retract prior to ground contact. Although modelling studies showed some active lengthening of the contractile (muscular) element during the mid-swing phase of high-speed running, we argue that the increasing distance between the attachment points should not be interpreted as an eccentric action of the CE due to the effects of muscle slack. Therefore, there may actually be no significant eccentric, but rather predominantly an isometric action of the hamstrings CE during the swing phase of high-speed running when the attachment points of the hamstrings are moving apart. Based on this, we propose that isometric rather than eccentric exercises are a more specific way of conditioning the hamstrings for high-speed running. 相似文献
19.
Geoffrey T. Burns Jessica Deneweth Zendler Ronald F. Zernicke 《Journal of sports sciences》2019,37(10):1129-1138
Ground reaction force measurements are a fundamental element of kinetic analyses of locomotion, yet they are traditionally constrained to laboratory settings or stationary frames. This study assessed the validity and reliability of a new wireless in-shoe system (Novel Loadsol/Pedoped) for field-based ground reaction force measurement in hopping, walking, and running. Twenty participants bilaterally hopped on a force plate and walked (5 km/hr) and ran (10 km/hr) on an instrumented treadmill on two separate days while wearing the insoles. GRFs were recorded simultaneously on each respective system. Peak GRF in hopping and peak GRF, contact time (CT), and impulse (IMP) in walking and running were compared on a per-hop and step-by-step basis. In hopping, the insoles demonstrated excellent agreement with the force plate (ICC: 0.96). In walking and running, the insoles demonstrated good-to-excellent agreement with the treadmill across all measures (ICCs: 0.88–0.96) and were reliable across sessions (ICCs within 0.00–0.03). A separate verification study with ten participants was conducted to assess a correction algorithm for further agreement improvement but demonstrated little meaningful change in systemic agreements. These results indicated that the Novel Loadsol system is a valid and reliable tool for wireless ground reaction force measurement in hopping, walking, and running. 相似文献
20.
Zhang S Derrick TR Evans W Yu YJ 《Sports biomechanics / International Society of Biomechanics in Sports》2008,7(2):296-309
Shock reduction has been well studied in moderate activities such as walking and running. However, there is a clear lack of research concerning shock wave transmission and reduction in more strenuous landing activities. In this study, we examined the impact of shock transmission and reduction in landing activities with varied mechanical demands. Ten active males were recruited for the study. They performed five successful step-off landing trials from each of five heights: 30, 45, 60, 75, and 90 cm. Right sagittal kinematics, ground reaction forces, and acceleration were recorded simultaneously. Impact frequencies were analysed using a discrete Fast Fourier Transform and power spectral density was computed. Increased range of motion for the ankle, knee, and hip joints was observed at higher landing heights. The peaks of the vertical ground reaction force, forehead and tibial accelerations, and eccentric muscle work by lower extremity joints were increased with increased landing heights. The peak head power spectral density was severely attenuated at higher frequencies but the peak tibia power spectral density did not demonstrate this trend. Shock reduction showed increased reduction at higher frequencies, but minimal changes across five landing heights. Unlike the responses observed for walking and running, the shock reduction did not show significant improvement with elevated mechanical demands. 相似文献