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1.
赛艇运动位移之流体力学理论浅析 总被引：2，自引：1，他引：1
王允民 《武汉体育学院学报》1994,(2)
有关赛艇技术文章对位移与流体理论相结合论述较少。本文应用流体力学之理论，对赛艇水中位移作深一步的探讨。通过理论推导与分析．描述了桨叶在水中划行的实际轨迹。论证了舟艇在水中产生运动全靠外力之作用，船速的快慢又取决于用力及桨划水角度。还提出技术准备动作滑坐反前进方向运动所产生的惯性阻力以及如何克服或将其减少到最低限度。 相似文献
2.
论赛艇动力学及提高赛艇技术的途径 总被引：6，自引：0，他引：6
用新型智能仪表SF2船速桨频测量仪采集数据,依据动量原理,建立赛艇动量方程及动力学方程。指出,桨手在滑座上移动时,人体质心动量变化产生的力在回桨和拉桨期都会各自交替产生动力和阻力,一般拉桨前期产生阻力,后期产生动力,回桨时相反。强调回桨质量,注意延长各段的动力作用时间,缩短阻力时间,加强低频训练和“意”练,让船速和桨频同步提高。 相似文献
3.
风速对划船运动成绩的影响 总被引：1，自引：0，他引：1
本文讨论了赛艇、皮划艇裸船的阻力构成,不同重量的运动员对阻力的影响,根据不同重量运动员的上体投影面积,在顺风或逆风下,不同风速对赛艇、皮划艇船速有较大影响。 相似文献
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5.
王允民 《武汉体育学院学报》1995,(1)
世界赛艇运动水平发展很快，对我国赛艇界在技术上提出了更高的要求。本文试图应用流体力学知识，结合数学物理方法，对赛艇技术进行理论性探讨，提供一种理解赛艇技术的新方法，并结合比赛中出现的几种主要技术问题，指出问题所在，提出了解决的办法。 相似文献
6.
赛艇技术诊断专家系统的开发与研究 总被引：4，自引：0，他引：4
闻兰 《上海体育学院学报》1999,(4)
采用计算机技术与赛艇技术诊断紧密结合的方法，开发了赛艇技术诊断专家系统，介绍了该系统的总体结构、知识处理、推理机制、解释方法等各种功能。 相似文献
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8.
本文对赛艇运动技术的研究进行了综述,从运动学,动力学和流体力学三个方面总结了我国对赛艇技术的研究,得出目前我国对赛艇技术研究的现状和存在的问题,并提出了今后赛艇运动技术研究的方向。 相似文献
9.
通过观察赛艇运动员在测功仪上的运动情况，记录其胫骨前肌、腓肠肌及股四头肌的肌电变化，对不同运动时期的表面肌电图、积分肌电（IEMG）和平均频谱进行了定量分析，结果表明：不同运动时期不同肌肉的神经肌电活动变化不完全一致，这为进一步了解赛艇运动特点、科学训练提供了参考。 相似文献
10.
单人皮划艇500m竞速结构与竞赛策略研究 总被引：1，自引：0，他引：1
通过对我国优秀皮划艇运动员测试数据的分析，提出了基于桨频曲线转折点的皮划艇500m比赛竞速结构划分方法；根据全程桨频和船速的变化特点，对每个阶段重新命名，更准确地反映了皮划艇500m竞速规律；冲刺阶段桨频的增加并不一定意味着船速的提高，船速是否增长取决于平均桨力，它才是船速的最终决定因素；对世界大赛中分段成绩的进行对比分析；以我国划艇运动员杨文军参加世界大赛成绩为例，说明了竞赛策略的重要性。 相似文献
11.
A. Millward 《Journal of sports sciences》2013,31(2):93-103
A model of the motion of a single‐scull rowing hull has been developed and verified against rowing performance data. The model was then used to explore the effect of changes in the cyclic rowing force on the boat speed. The calculations have shown that the shape of the rowing force curve and the proportion of recovery time in the total stroke can have an important effect on the boat speed. It has also been shown that a study of the fluid mechanics of the oar blade would be advantageous in determining whether a reduction in the power wasted can be obtained by changing the ratio of rowing force to normal force. 相似文献
12.
Erica M. Buckeridge Anthony M.J. Bull Alison H. McGregor 《Journal of sports sciences》2016,34(4):369-378
Lumbar-pelvic kinematics change in response to increasing rowing stroke rates, but little is known about the effect of incremental stroke rates on changes in joint kinetics and their implications for injury. The purpose of this study was to quantify the effects of incremental rowing intensities on lower limb and lumbar-pelvic kinetics. Twelve female rowers performed an incremental test on a rowing ergometer. Kinematic data of rowers’ ankle, knee, hip and lumbar-pelvic joints, as well as external forces at the handle, seat and foot-stretchers of the rowing machine were recorded. Inter-segmental moments and forces were calculated using inverse dynamics and were compared across stroke rates using repeated measures ANOVA. Rowers exhibited increases in peak ankle and L5/S1 extensor moments, reductions in peak knee moments and no change in peak hip moments, with respect to stroke rate. Large shear and compressive forces were seen at L5/S1 and increased with stroke rate (P < 0.05). This coincided with increased levels of lumbar-pelvic flexion. High levels of lumbar-pelvic loading at higher stroke rates have implications with respect to injury and indicated that technique was declining, leading to increased lumbar-pelvic flexion. Such changes are not advantageous to performance and can potentially increase the risk of developing injuries. 相似文献
13.
A Millward 《Journal of sports sciences》1987,5(2):93-103
A model of the motion of a single-scull rowing hull has been developed and verified against rowing performance data. The model was then used to explore the effect of changes in the cyclic rowing force on the boat speed. The calculations have shown that the shape of the rowing force curve and the proportion of recovery time in the total stroke can have an important effect on the boat speed. It has also been shown that a study of the fluid mechanics of the oar blade would be advantageous in determining whether a reduction in the power wasted can be obtained by changing the ratio of rowing force to normal force. 相似文献
14.
A mathematical model relating power output of rower to stroke rate on an ergometer (the Concept II Indoor Rower TM, Model
C) is studied. The model is used to analyse the ergometer performance of a particular rower. It is determined that he can
be more efficient (i.e. decrease power output while maintaining fixed velocity) by decreasing stroke rate, but at the expense
of increasing force during the drive. It is also shown that he can be more efficient by increasing the drag factor (using
higher vent setting) without increasing force. Dependence of power output on rowing style (the shape of the force curve) is
also examined. It is shown that variation of force during the drive has little effect on efficiency, but efficiency is reduced
by asymmetry of the force curve that favours the legs. 相似文献
15.
Lotte L. Lintmeijer Mathijs J. Hofmijster Guido A. Schulte Fischedick Patrick J. Zijlstra A. J. “Knoek” Van Soest 《Journal of sports sciences》2018,36(18):2138-2146
In rowing, mechanical power output is a key parameter for biophysical analyses and performance monitoring and should therefore be measured accurately. It is common practice to estimate on-water power output as the time average of the dot product of the moment of the handle force relative to the oar pin and the oar angular velocity. In a theoretical analysis we have recently shown that this measure differs from the true power output by an amount that equals the mean of the rower’s mass multiplied by the rower’s center of mass acceleration and the velocity of the boat. In this study we investigated the difference between a rower’s power output calculated using the common proxy and the true power output under different rowing conditions. Nine rowers participated in an on-water experiment consisting of 7 trials in a single scull. Stroke rate, technique and forces applied to the oar were varied. On average, rowers’ power output was underestimated with 12.3% when determined using the common proxy. Variations between rowers and rowing conditions were small (SD = 1.1%) and mostly due to differences in stroke rate. To analyze and monitor rowing performance accurately, a correction of the determination of rowers’ on-water power output is therefore required. 相似文献
16.
Erica M. Buckeridge Robert A. Weinert-Aplin Anthony M. J. Bull Alison H. McGregor 《Sports biomechanics / International Society of Biomechanics in Sports》2016,15(4):513-526
Strength, technique, and coordination are crucial to rowing performance, but external interventions such as foot-stretcher set-up can fine-tune technique and optimise power output. For the same resultant force, raising the height of foot-stretchers on a rowing ergometer theoretically alters the orientation of the resultant force vector in favour of the horizontal component. This study modified foot-stretcher heights and examined their instantaneous effect on foot forces and rowing technique. Ten male participants rowed at four foot-stretcher heights on an ergometer that measured handle force, stroke length, and vertical and horizontal foot forces. Rowers were instrumented with motion sensors to measure ankle, knee, hip, and lumbar–pelvic kinematics. Key resultant effects of increased foot-stretcher heights included progressive reductions in horizontal foot force, stroke length, and pelvis range of motion. Raising foot-stretcher height did not increase the horizontal component of foot force as previously speculated. The reduced ability to anteriorly rotate the pelvis at the front of the stroke may be a key obstacle in gaining benefits from raised foot-stretcher heights. This study shows that small changes in athlete set-up can influence ergometer rowing technique, and rowers must individually fine-tune their foot-stretcher height to optimise power transfer through the rowing stroke on an ergometer. 相似文献
17.
双人赛艇兴波阻力特性分析 总被引：3，自引：2，他引：1
采用Michell积分计算赛艇兴波阻力，得到了赛艇兴波阻力随航速的变化规律。将本文计算结果与用三维Rankine源面元法计算得到的赛艇兴波阻力相比较，结果表明Michell积分是一种计算赛艇高速下兴皮阻力的简单实用方法。还分析了双人赛艇兴波阻力和所需功率随体重的变化特性。 相似文献
18.
划艇500M单划全程技术分析 总被引：3，自引：0，他引：3
运用运动生物力学的研究方法，使用Ｍ９０００摄像机（每秒２５帧）和ＳＴＤ－１型影片解析仪，对武汉体育学院划艇运员张某１９９４年８月训练时划艇５００Ｍ单划技术进行影像分析。研究结果表明：他在５００Ｍ全程技术中特点为：起航阶段速度４．３５Ｍ／ｓ；途中阶段速度为４．２５Ｍ／ｓ；冲刺阶段速度为３．８５Ｍ／ｓ，与２１届奥运会划艇５００Ｍ单划起航阶段速度相等，他的途中划阶段的划速略比２１届奥运会记录的途中划速度４．１９Ｍ／ｓ要高。这两个阶段的浆频稳定在６７浆／分左右，划幅约为３．８Ｍ／浆，前２５０Ｍ共用时５８Ｓ多。冲刺阶段浆频虽然高达６８浆／分，划幅却只有约３Ｍ／浆，因此船速较低，造成后２５０Ｍ用时达６４Ｓ之多。因此提高冲刺阶段速度，则显得尤为重要。 相似文献
19.
赛艇运动中拉桨阶段的桨力曲线反映了运动员的发力特征，是专项竞技能力诊断的重要途径。根据国家队的测试实例，对不同艇种、不同桨位的桨力曲线特征进行归纳分析总结，对赛艇项目进行系列测试（桨频：35桨/min），结合专项认为专项技术较好的多人艇运动员大多采用A型；双人单桨项目中．领桨手倾向于采用A型桨力-时间曲线，一号位桨手倾向于采用B型桨力-时间曲线。不同桨频下的桨力-时间曲线特征可作为训练效果的评估依据，低桨频训练必须保持合理的拉桨速度和拉桨力量。 相似文献
20.
The relationship between selected physiological variables of rowers and rowing performance as determined by a 2000 m ergometer test 总被引：6，自引：0，他引：6
The aim of this study was to establish the relationship between selected physiological variables of rowers and rowing performance as determined by a 2000 m time-trial on a Concept II Model B rowing ergometer. The participants were 13 male club standard oarsmen. Their mean (+/- s) age, body mass and height were 19.9+/-0.6 years, 73.1+/-6.6 kg and 180.5+/-4.6 cm respectively. The participants were tested on the rowing ergometer to determine their maximal oxygen uptake (VO2max), rowing economy, predicted velocity at VO2max, velocity and VO2 at the lactate threshold, and their velocity and VO2 at a blood lactate concentration of 4 mmol x l(-1). Percent body fat was estimated using the skinfold method. The velocity for the 2000 m performance test and the predicted velocities at the lactate threshold, at a blood lactate concentration of 4 mmol x l(-1) and at VO2max were 4.7+/-0.2, 3.9+/-0.2, 4.2+/-0.2 and 4.6+/-0.2 m x s(-1) respectively. A repeated-measures analysis of variance showed that the three predicted velocities were all significantly different from each other (P<0.05). The VO2max and lean body mass showed the highest correlation with the velocity for the 2000 m time-trial (r = 0.85). A stepwise multiple regression showed that VO2max was the best single predictor of the velocity for the 2000 m time-trial; a model incorporating VO2max explained 72% of the variability in 2000 m rowing performance. Our results suggest that rowers should devote time to the improvement of VO2max and lean body mass. 相似文献