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运动高速摄影和跑台气体代谢法对男子中长跑运动员进行了研究.通过测定运动员1500 m跑步过程中身体各环节输出功,发现运动员身体各环节输出功的比例关系为:摆动腿占比例最大,其次是支撑腿,上肢和躯干的输出功的比例相当,头部所占比例很小.运动员跑步过程中,环节内和环节之间存在能量转换,且环节之间能量转换是主要的. 相似文献
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优秀背越式跳高运动员起跳阶段若干运动学参数的统计分析 总被引：3，自引：0，他引：3
一、前言起跳是跳高最关键的技术环节。它衔接着助跑和腾越过杆。助跑阶段运动员积累的能量不仅通过起跳转化为腾起的能量,而且背越技术所特有的转体动量矩和旋转过杆动量矩皆由起跳动作而转换。起跳阶段的动作结构十分复杂,它包括起跳腿和摆动腿以及上肢摆动的动作,另外,转体的形成还与躯干的动作例如肩轴和髋轴交叉的时空结构有关,但这一系列动作的形成和调整,无一不与起跳阶段运动员身体重心的高度及其变化和身体的倾斜角度及角度的变化有关。在技术分析中,它们虽然仅作为运动学参量出 相似文献
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作者以五名男子跳远运动员和一名女子跳远运动员为实验对象,研究了机械功、机械能转换及跑速之间的关系。以100格/秒的速度,用Locam高速摄影机拍摄了实验对象们的最大及次最大跳远动作。用机械能曲线计算了身体环节内的能量转换及动能和势能间的转换。这是由机械功按三种方法计算出的:Wn-无能量转 相似文献
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黄文武 《山东体育学院学报》2006,22(3):52-55
跑步运动是相当复杂的能量转换和动力学过程。建立跑步时能量转换的数学关系对于运动训练乃至运动生物力学都具有积极意义,可惜至今还未获圆满解决。Keller于1973年建立了跑步动力学方程,提出了跑动动力、跑动速度、地面阻力和空气阻力之间的关系。后来有人以此为依据,建立了跑 相似文献
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一、单人项目运动员的科学选材单人项目运动员选材测试的内容主要有以下几个方面: 1.身体形态身体形态主要是指身高、体重、四肢躯干的长度、围度、肩宽以及身体各部分的比例关系等。身体形态的具体指标很多,根据我国优秀单跳运动员的身体形态看,我们一般选拔身体匀称,臂腿要直,跟腱细长 相似文献
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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
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在自由泳的游进过程中,划手起着主要的推进作用,打腿产生的推进力较小,且打腿消耗的氧气更多。除了会产生推进力,自由泳打腿还会被一些教练认为可以保持身体的平衡。如果腿部下沉,阻力增大的同时还会消耗更多的能量,因此,打腿技术好的运动员身体位置较高。此外,快速的打腿动作能够将兴奋;中动反馈到中枢神经系统,使其发放更多的神经冲动,加快手臂动作,调节频率。 相似文献
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短跑运动员途中跑支撑期摆动腿作用的运动学相关分析 总被引：2，自引：0，他引：2
为研究短跑运动员途中跑支撑阶段摆动腿对跑速的影响 ,采用高速摄影及影片解析、数理统计等方法 ,对我国短跑运动员途中跑支撑期摆动腿运动学特征等指标与身体重心速度、专项成绩之间的关系进行分析。结果表明 :途中跑中摆动腿最大摆动速度和平均摆动速度与支撑腿支撑时间显著相关 ,摆动腿的平均摆动速度与后蹬时间之间明显相关 ;摆动腿的摆动角速度与身体重心水平速度及垂直速度密切相关 ;支撑腿和摆动腿的角速度变化量与离地瞬间身体重心水平速度密切相关。提示 :加快摆动腿的摆动速度能有效提高缓冲和蹬伸速度 ,缩短支撑时间 ,提高途中跑的步频 ;摆动腿的摆动速度对加快身体重心水平速度有显著影响 ;加强和提高途中跑摆动腿的运动效果 ,提高短跑运动员下肢摆动工作肌群的力量。 相似文献
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Six Danish male cross-country skiers were studied during the end-of-summer and winter seasons. Their maximal oxygen uptake was measured while running on a treadmill and using a ski ergometer incorporating the double-poling technique. Maximal oxygen uptake during treadmill running and double-poling was correlated with performance, expressed as a ranking score during 10 ski races. The tests were undertaken in September, December and April. Upper body maximal oxygen uptake increased 5.8% from September to December, decreasing to 2.3% above the September level in April. Upper body work output (2 min at maximal intensity) increased 11.8% from September to December (P less than 0.05). The relationship between upper body and leg maximal oxygen uptake--the upper body/leg ratio--was 89.4% in September. In four skiers, both treadmill and upper body tests were undertaken on each test occasion. The upper body/leg ratio changed from 87.7% in September to 95.7% in December. In April, the ratio was 91.0%. The maximal oxygen uptake measured using the ski ergometer during double-poling was significantly correlated with performance (P less than 0.05). It is concluded that the upper body ski ergometer can be used in the evaluation of elite cross-country skiers. 相似文献
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目的:研究走、跑模式下健康成年男子单位时间单位体重的能量消耗与运动速度的相关关系以及单位距离单位体重的能量消耗与运动速度的相关关系;探讨相同速度走、跑两种不同的运动模式下能量消耗特征;方法:19名男性大学生作为研究对象。使用跑台控制速度,采用走、跑两种运动模式,每一速度至少测试6min,以速度递增的方式进行测试,走、跑模式转换时休息至安静状态。使用VO2000测试安静以及运动中的气体代谢参数,PO-LAR表测试心率;结果:建立走模式以及跑模式下的能量消耗与速度之间的拟合方程;单位时间单位体重的能耗与走速二次曲线拟合方程的复相关系数r2=0.88;单位时间单位体重的能耗与跑速线性拟合方程的复相关系数r2=0.72;两条拟合曲线的交点坐标为(2.35m/s,141.7cal/kg/min);在测试速度范围之内,同等速度下走与跑的单位时间的能耗具有显著性差异(P<0.01),跑的能耗显著大于走的能耗。单位距离单位体重的能耗与走速的2次拟合曲线的复相关系数r2=0.98,曲线最低点的坐标为(1.14m/s,0.553cal/kg/m),单位距离单位体重的平均能耗与跑速拟合曲线的复相关系数r2=0.68;结论:1)单位时间单位体重的能耗与走速呈二次曲线关系,单位时间单位体重的能耗与跑速呈线性递增关系;2)单位距离单位体重的能耗与走速呈"U"型曲线关系;单位距离单位体重的能耗与跑速呈线性递减趋势,说明在一定速度范围内随着跑速的增加单位距离单位体重的能耗降低。 相似文献
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Gianluca Vernillo Aldo Savoldelli Andrea Zignoli Spyros Skafidas Alessandro Fornasiero Antonio La Torre 《Journal of sports sciences》2015,33(19):1998-2005
This study aimed to determine whether the fatigue induced by a mountain ultramarathon (MUM) led to changes in energy cost and kinematic during level and graded running. Pre- and post-race, 14 ultratrail runners ran on a level, uphill (5%) and downhill (5%) treadmill at 10 km · h?1. Kinematic data were acquired using a photocell system. Post-race, the downhill energy cost increased by 13.1% (P < 0.001). No change was noted in level and uphill running. Duty factor and stride frequency were increased, whereas swing time, cycle time and stride length were decreased in all conditions (P < 0.05). Contact time was increased and the rate of force generation was decreased only in the uphill and downhill conditions (P < 0.05). Positive correlations were observed between performance time and the pre- to post-changes in the energy cost of level (r = 0.52, P = 0.04) and uphill running (r = 0.50, P = 0.04). MUM-induced fatigue resulted in physiological and spatiotemporal changes, though the response to fatigue varied considerably between running conditions. These changes resulted in a significant increment only in the downhill energy cost. Incorporating downhill locomotion in the training programmes of ultratrailers may help to improve performance-related physiological and biomechanical parameters. 相似文献
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As a wide range of values has been reported for the relative energetics of 400-m and 800-m track running events, this study aimed to quantify the respective aerobic and anaerobic energy contributions to these events during track running. Sixteen trained 400-m (11 males, 5 females) and 11 trained 800-m (9 males, 2 females) athletes participated in this study. The participants performed (on separate days) a laboratory graded exercsie test and multiple race time-trials. The relative energy system contribution was calculated by multiple methods based upon measures of race [Vdot]O2, accumulated oxygen deficit (AOD), blood lactate and estimated phosphocreatine degradation (lactate/PCr). The aerobic/anaerobic energy system contribution (AOD method) to the 400-m event was calculated as 41/59% (male) and 45/55% (female). For the 800-m event, an increased aerobic involvement was noted with a 60/40% (male) and 70/30% (female) respective contribution. Significant (P <?0.05) negative correlations were noted between race performance and anaerobic energy system involvement (lactate/PCr) for the male 800-m and female 400-m events (r = ? 0.77 and ??0.87 respectively). These track running data compare well with previous estimates of the relative energy system contributions to the 400-m and 800-m events. Additionally, the relative importance and speed of interaction of the respective metabolic pathways has implications to training for these events. 相似文献
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Claudia Knoepfli-Lenzin Jennifer Carole Waech Turgut Gülay Florian Schellenberg Silvio Lorenzetti 《Journal of sports sciences》2013,31(18):1671-1679
AbstractRunning shoe construction influences the forces experienced by the human body while running. The aim of this study was to ascertain whether the new sole architecture of the On running shoe reduces ground reaction forces compared with running barefoot or with a conventional running shoe and whether it changes the physiological parameters of running in shoes. Thirty-seven trained male participants were studied while running at submaximal speeds wearing their conventional running shoe, wearing the On running shoe and while barefoot. Additional biomechanical and physiological values were investigated to determine whether the On running shoe induced any changes in these parameters compared with conventional running shoes. The On exhibited similar ground reaction forces as conventional shoes, and these were different from the forces experienced while running barefoot, showing that the On was more similar to typical shoed running. No difference was observed in running economy between the On and a conventional shoe model. However, a slightly lower heart rate (HR) (≈1.3%) and blood lactate concentration (≈5.5%) were observed during submaximal running with the On running shoe compared with a conventional running shoe, as well as a greater lateral deviation of the centre of pressure mid-stance. The ramifications of the reduced HR and blood lactate concentration for competitive performance are unknown. 相似文献
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《Journal of sports sciences》2012,30(1):6-12
ABSTRACTThis study aimed to examine the characteristics of electromyography (EMG) and kinematics of the supporting leg affecting energy cost while running at incline, level, and decline slopes. Twelve male Japanese middle- and long-distance runners volunteered for this study. The subjects were asked to run at 13.5 km·h?1 on a treadmill under three slope conditions. Sagittal plane kinematics and the EMG of the lower limb muscles, respiratory gases were recorded. Energy cost differed significantly between slopes, being the lowest in decline slope and the greatest in incline slope. Integrated EMG (iEMG) of leg extensor muscles was greater in the incline slope than in the decline slope, and iEMG of the gastrocnemius and soleus muscles correlated positively with energy cost. The knee and ankle joint kinematics were associated with energy cost during running. In incline slope, the knee and ankle joints were more extended (plantarflexed) to lift the body. These movements may disturb the coordination between the ankle and knee joints. The gastrocnemius muscle would do greater mechanical work to plantarflex the ankle joint rather than transfer mechanical energy as well as greater mechanical work of mono-articular muscles. These muscular activities would increase energy cost. 相似文献
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Debbie Risius Alexandra Milligan Jason Berns Nicola Brown 《Journal of sports sciences》2017,35(9):842-851
To assess the effectiveness of breast support previous studies monitored breast kinematics and kinetics, subjective feedback, muscle activity (EMG), ground reaction forces (GRFs) and physiological measures in isolation. Comparing these variables within one study will establish the key performance variables that distinguish between breast supports during activities such as running. This study investigates the effects of changes in breast support on biomechanical, physiological and subjective measures during running. Ten females (34D) ran for 10 min in high and low breast supports, and for 2 min bare breasted (2.8 m·s?1). Breast and body kinematics, EMG, expired air and heart rate were recorded. GRFs were recorded during 10 m overground runs (2.8 m·s?1) and subjective feedback obtained after each condition. Of the 62 variables measured, 22 kinematic and subjective variables were influenced by changes in breast support. Willingness to exercise, time lag and superio-inferior breast velocity were most affected. GRFs, EMG and physiological variables were unaffected by breast support changes during running. Breast displacement reduction, although previously advocated, was not the most sensitive variable to breast support changes during running. Instead breast support products should be assessed using a battery of performance indicators, including the key kinematic and subjective variables identified here. 相似文献
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Lower limb joint kinetics in the starting blocks and first stance in athletic sprinting 总被引：1，自引：1，他引：0
Adam Brazil Timothy Exell Cassie Wilson Steffen Willwacher Ian Bezodis Gareth Irwin 《Journal of sports sciences》2017,35(16):1629-1635
The aim of this study was to examine lower limb joint kinetics during the block and first stance phases in athletic sprinting. Ten male sprinters (100 m PB, 10.50 ± 0.27 s) performed maximal sprint starts from blocks. External force (1000 Hz) and three-dimensional kinematics (250 Hz) were recorded in both the block (utilising instrumented starting blocks) and subsequent first stance phases. Ankle, knee and hip resultant joint moment, power and work were calculated at the rear and front leg during the block phase and during first stance using inverse dynamics. Significantly (P < 0.05) greater peak moment, power and work were evident at the knee joint in the front block and during stance compared with the rear block. Ankle joint kinetic data significantly increased during stance compared with the front and rear block. The hip joint dominated leg extensor energy generation in the block phase (rear leg, 61 ± 10%; front leg, 64 ± 8%) but significantly reduced during stance (32 ± 9%), where the ankle contributed most (42 ± 6%). The current study provides novel insight into sprint start biomechanics and the contribution of the lower limb joints towards leg extensor energy generation. 相似文献
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Stephen Patterson John Pattison Hayley Legg Ann-Marie Gibson Nicola Brown 《Journal of sports sciences》2017,35(11):1098-1106
The purpose of the study was to examine the health effects of 8 weeks of recreational badminton in untrained women. Participants were matched for maximal oxygen uptake (V?O2max) and body fat percentage and assigned to either a badminton (n = 14), running (n = 14) or control group (n = 8). Assessments were conducted pre- and post-intervention with physiological, anthropometric, motivation to exercise and physical self-esteem data collected. Post-intervention, V?O2max increased (P < 0.05) by 16% and 14% in the badminton and running groups, respectively, and time to exhaustion increased (P < 0.05) by 19% for both interventions. Maximal power output was increased (P < 0.05) by 13% in the badminton group only. Blood pressure, resting heart rate and heart rate during submaximal running were lower (P < 0.05) in both interventions. Perceptions of physical conditioning increased (P < 0.05) in both interventions. There were increases (P < 0.05) in enjoyment and ill health motives in the running group only, whilst affiliation motives were higher (P < 0.05) for the badminton group only. Findings suggest that badminton should be considered a strategy to improving the health and well-being of untrained females who are currently not meeting physical activity guidelines. 相似文献
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Hannelore Boey Jeroen Aeles Kurt Schütte Benedicte Vanwanseele 《Sports biomechanics / International Society of Biomechanics in Sports》2017,16(2):166-176
Research has focused on parameters that are associated with injury risk, e.g. vertical acceleration. These parameters can be influenced by running on different surfaces or at different running speeds, but the relationship between them is not completely clear. Understanding the relationship may result in training guidelines to reduce the injury risk. In this study, thirty-five participants with three different levels of running experience were recruited. Participants ran on three different surfaces (concrete, synthetic running track, and woodchip trail) at two different running speeds: a self-selected comfortable speed and a fixed speed of 3.06 m/s. Vertical acceleration of the lower leg was measured with an accelerometer. The vertical acceleration was significantly lower during running on the woodchip trail in comparison with the synthetic running track and the concrete, and significantly lower during running at lower speed in comparison with during running at higher speed on all surfaces. No significant differences in vertical acceleration were found between the three groups of runners at fixed speed. Higher self-selected speed due to higher performance level also did not result in higher vertical acceleration. These results may show that running on a woodchip trail and slowing down could reduce the injury risk at the tibia. 相似文献