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1.
目的:探索在连续纵跳下落阶段优势侧和非优势侧踝关节的运动学、地面反作用力差异.方法:采用13名健康男性作为受试者,每名受试者进行连续纵跳5次,以起跳时的重心高度作为标准,选取5次中最好成绩动作的下落阶段进行分析.运动过程中采集两侧下肢的地面反作用力以及两侧踝关节的运动学数据,利用配对t检验对所采集的两侧数据进行分析.结果:在连续纵跳的下落阶段,优势侧踝关节的背屈方向和外旋方向上的角速度、垂直方向上的地面反作用力均大于非优势侧(P＜0.05),但踝关节的其他运动学、动力学指标均没有显著性差异.结论:在连续纵跳的下落阶段,与优势侧相比,非优势侧可能在屈伸与外旋方向有较大的运动限制,而与非优势侧相比,优势侧在下落着地过程中出现运动损伤的可能性较大.  相似文献   

2.
目的:确定运动员在落地后即刻启动完成侧切变向(LSC)动作的下肢踝、膝和髋三关节矢状面的运动学和动力学特点,并与平地跑动侧切变向(SC)对比分析、探讨这些差异对下肢关节造成的影响。方法:以14名高水平足球运动员为背景的大学生完成落地侧切和平跑侧切动作时的下肢运动学和动力学数据进行采集与分析。结果:LSC动作的踝、膝关节ROM和关节角速度显著增加,髋关节ROM则呈相反趋势(P<0.05或P<0.01);LSC的踝、膝和髋关节力矩峰值,踝、髋关节功率峰值呈现显著大于SC(P<0.01),膝关节功率峰值小于SC(P<0.05);LSC在水平向后、垂直向上地反峰值及峰值加载率有明显的增加(P<0.01),水平向右地反无明显差异(P>0.05)。结论:LSC虽然略降低了膝关节功率峰值,但其余所有运动学、动力学及GRF都预示其下肢关节所承受的损伤风险更高,尤其是踝关节和膝关节。踝关节的高功率和跖屈肌的持续紧张、伸膝力矩和三维地反的显著升高,使得该动作比公认高损伤风险的平跑侧切损伤风险几率更大。  相似文献   

3.
探求鞭腿技术击打不同类型目标时因动作运用不当可能引发膝关节运动损伤的危险时刻。运用VICON System 3D运动采集系统,对10名优秀散打运动员鞭腿技术进行空击、击打脚靶、沙包时的运动轨迹进行采集,依据鞭打动作特点和下肢关节运动特征,将鞭腿动作划分为3个时刻、2个时段,对其在各时刻的动作速度、作用腿膝关节角度、角速度、力矩等运用VICON Nexus和Polygon分析软件进行处理。研究结果表明:作用腿膝关节屈伸、内收外展、回旋角度和角速度以及关节力矩等各方面均存在着显著性差异(P<0.05);鞭腿空击技术类型的动作速度相对较慢,击打时段膝关节角速度相对较快、伸展时段膝关节呈外旋、加速并过度伸展状态;击打脚靶类型的动作速度相对较快,伸展时段膝关节呈外旋伸展运动状态;击打沙包类型膝关节的各项力矩相对较大,伸展时段膝关节呈反方向运动状态。鞭腿的3种击打类型均存在引发膝关节运动损伤的危险时刻,建议运动员在训练和实战时遵循鞭腿技术动作的运动规律。  相似文献   

4.
目的:对辽宁省排球队女运动员下肢急停纵跳落地时的力矩和最大关节角度进行研究,以期对有膝关节损伤的排球运动员进行科学训练提供参考。方法:以14名辽宁省排球队女运动员为研究对象,将运动员分为两组,其中无伤组8人,损伤组6人,采用三维测力平台和红外光电运动捕捉系统,记录受试者在完成急停纵跳动作落地时的髋关节、膝关节、踝关节的力矩以及最大关节角度数据。结果:在急停纵跳落地时,损伤膝关节的旋转、收展力矩大于无伤组,屈伸力矩小于无伤组,损伤组的髋关节的屈伸、收展、旋转力矩均大于无伤组;损伤组的踝关节旋转力矩小于无伤组,收展力矩和屈伸力矩大于无伤组。损伤组的踝关节在屈伸、收展和旋转时的最大关节角度大于无伤组;损伤组的膝关节在屈伸和收展时的最大关节角度大于无伤组,旋转时小于无伤组;损伤的髋关节屈伸和收展时的最大关节角度大于无伤组,髋关节旋转时的最大关节角度左侧小于无伤组,右侧大于无伤组。结论:膝关节损伤的运动员完成急停纵跳动作落地时,通过代偿性改变增大髋关节力矩、增加膝关节旋转和收展力矩,增大踝关节收展和屈伸力矩,增加膝关节和髋关节在屈伸和收展时活动角度,增加膝关节屈伸和收展时活动角度来完成动作。  相似文献   

5.
采用CYBEX6000等速测力仪,对30名优秀的速滑运动员髋关节屈伸肌群峰值力矩、平均功率、总功输出及屈/伸肌比值(%)进行了比较与分析。结果表明:双髋关节屈伸肌峰值力矩、总功输出均随角速度增加而下降,平均功率则升高;同一速度区髋关节屈伸肌的峰值力矩、平均功率、总功伸肌大于屈肌;不同速度区伴有"优势交换"现象,即低速区左侧屈伸肌大于右侧,高速区则以右侧伸肌增强为主。速滑运动员髋关节屈/伸肌比值(%)随角速度增加而下降。  相似文献   

6.
目的:评估下肢优势侧和非优势侧20m×5负重往返跑对下肢爆发力产生的影响。方法:采用随机交互设计,14名健康男性受试者分别完成2次20m×5负重往返跑,分别在运动后即刻和20min进行下肢爆发能力测试,并记录RR间期。结果:与安静状态相比,优势侧和非优势负重运动后,心率、运动后过氧消耗和运动冲量均显著增加(P<0.01),但优势侧和非优势侧之间不存在显著差异(P>0.05);与安静值相比,优势侧和非优势侧运动后即刻整体表现下肢爆发力纵跳高度显著降低(P<0.05),同样的,最小作用力、垂直蹬伸速度和腾空时间在运动后即刻显著下降(P<0.05),但两者之间不存在显著差异(P>0.05),其余动力学指标运动前后不存在显著差异(P>0.05);运动后20min内均除平均速度显著增加外(P<0.05),其余指标均恢复到安静状态(P>0.05)与安静值相比,优势侧和非优势侧运动后即刻整体、前后和左右方向摆动均显著增加(P<0.05),但两者之间不存在显著差异。运动后20min内均恢复到安静状态(P>0.05)。整体上,表明单侧负重,下肢优势侧和非优势侧爆发力能力的波动程度相同。结论:下肢优势侧不影响运动后即刻和运动后恢复期爆发力的变化。  相似文献   

7.
目的主要运用生物力学的方法研究不同踝关节保护措施对足球运动员侧切时支撑腿力学特征的影响。方法运用红外光点运动捕捉系统同步三维测力台,对足球运动员在不采取踝关节保护措施、贴扎和佩带护具3种状态下侧切过程中支撑腿有关力学参数进行分析。结果在侧切过程中,贴扎缩短了受试者从接触地面到达首次垂直地面反作用力峰值的时间,减小了足最大背屈角度、最大内翻角度和最大内翻角速度;护具显著减小了足最大背屈角度,明显增加了最大内翻角度和踝关节最大外翻力矩。结论贴扎能有效地减小踝关节活动度,但使人体侧切着地初期缓冲能力下降;贴扎能为人体保护机制提供更多的时间来应对踝内翻,也许会减少踝关节潜在的损伤。护具能有效地限制了踝的屈伸活动度。二者的使用并未对膝关节带来消极影响。  相似文献   

8.
目的：探讨3种不同方向(前跳、斜跳与侧跳)单腿跳跃落地侧切变向及运动疲劳对踝关节扭伤风险的影响。方法：采用红外运动捕捉系统与三维测力台,同步采集15名男性大学生业余球类运动者在疲劳前后完成3种不同方向单腿跳跃落地侧切变向动作时的运动学和动力学指标。结果：在触地时刻,不同方向落地侧切时踝跖屈角度和踝内翻角速度之间存在显著差异,表现为侧跳最大,前跳最小在缓冲阶段中,最大踝内翻角、最大踝内翻角速度、最大踝内翻力矩和最大垂直地面反作用力指标在不同方向落地侧切时存在显著性差异,表现侧跳最大,前跳最小。疲劳前后不同方向落地侧切的各项指标中均无显著性差异。结论：不同方向落地侧切动作可对踝关节动作模式造成影响,侧切变向角度增加可能导致更高的踝关节扭伤风险。运动疲劳可能不会增大男子落地侧切动作踝关节损伤风险。  相似文献   

9.
分别选择男女运动员各10名做变向跑运动(n=10次),记录其触地初期的髋、膝和踝的关节角度以及膝外展力矩,并对主要的性别影响因素做了方差分析.研究结果表明,女性的标准化膝外展力矩显著大于男性.初始髋关节弯曲和内侧旋转越大,则外展力矩的峰值越大;初始的膝外展角度越大,外展力矩的峰值越大.  相似文献   

10.
运用文献资料法、实验法和数理统计法,以10名辽宁省排球队女运动员为研究对象,获取受试者3步助跑后衔接跳跃扣球的起跳期在三维空间坐标中的轨迹和与地面的反作用力参数,以及髋关节、膝关节、踝关节的最大伸肌力矩和最大伸肌功率,研究排球不同扣球起跳下肢运动学的特征,为提高排球扣球起跳时的动作质量提供参考。结果表明:(1)后排先行脚、跟随脚的动作时间、动作总时间短于后排,后排起跳动作距离长于前排(P<0.01);(2)先行脚和跟随脚的髋关节、膝关节伸肌力矩后排大于前排(P>0.05);在踝关节伸肌力矩中,后排的先行脚大于前排(P>0.05),后排的跟随脚大于前排(P<0.05);(3)除先行脚的膝关节向心功率后排均小于前排外,先行脚和跟随脚的髋关节、膝关节、踝关节伸肌向心功率后排均大于前排。先行脚和跟随脚的髋关节、膝关节肌坏踝关节离心功率后排大于前排。  相似文献   

11.
The aim of the present study was to examine the relationships between muscle cross-sectional area (CSA) and muscular strength in terms of knee extension and flexion, hip extension and flexion, and hip abduction and adduction among well-trained soccer players. Fourteen university soccer players participated in the study, who had previously been divided into two groups based on ability (Group A: above-average ability; Group B: average ability). Maximal isokinetic and concentric muscular strength was measured in knee extension/flexion, hip extension/flexion and hip abduction/adduction using an isokinetic dynamometer at 1.57 and 4.19 rad x s(-1) (3.14 rad x s(-1)) in both the dominant and non-dominant leg. The CSAs of the thigh, gluteus muscles and iliopsoas muscles were calculated based on magnetic resonance imaging. There was no significant difference between the two groups in muscle CSA and isokinetic strength. Although there were some statistically significant differences between the dominant and non-dominant leg in terms of CSA and strength (P < 0.05-0.01), these were small and negligible. Apart from a non-significant relationship between the CSAs of the adductor muscles and hip adductor strength (r < 0.26, N.S.), the CSA of the other muscle groups correlated with maximal isokinetic strength (r = 0.38-0.64, P < 0.05). These results suggest that no difference in muscle characteristics (in terms of muscle CSA and strength) was apparent among well-trained soccer players, even between the dominant and non-dominant leg. There is also a case that the anatomical function of a single (or group of) muscle(s) may not be reflected by the strength-CSA relationship depending on the movements (such as hip adduction-adductor muscle CSA). Thus, further studies are required to develop methods to assess neuromuscular function in relation to muscle morphology among soccer players.  相似文献   

12.
Abstract

The aim of the present study was to examine the relationships between muscle cross-sectional area (CSA) and muscular strength in terms of knee extension and flexion, hip extension and flexion, and hip abduction and adduction among well-trained soccer players. Fourteen university soccer players participated in the study, who had previously been divided into two groups based on ability (Group A: above-average ability; Group B: average ability). Maximal isokinetic and concentric muscular strength was measured in knee extension/flexion, hip extension/flexion and hip abduction/adduction using an isokinetic dynamometer at 1.57 and 4.19 rad·s?1 (3.14 rad·s?1) in both the dominant and non-dominant leg. The CSAs of the thigh, gluteus muscles and iliopsoas muscles were calculated based on magnetic resonance imaging. There was no significant difference between the two groups in muscle CSA and isokinetic strength. Although there were some statistically significant differences between the dominant and non-dominant leg in terms of CSA and strength (P<0.05–0.01), these were small and negligible. Apart from a non-significant relationship between the CSAs of the adductor muscles and hip adductor strength (r<0.26, n.s.), the CSA of the other muscle groups correlated with maximal isokinetic strength (r=0.38–0.64, P<0.05). These results suggest that no difference in muscle characteristics (in terms of muscle CSA and strength) was apparent among well-trained soccer players, even between the dominant and non-dominant leg. There is also a case that the anatomical function of a single (or group of) muscle(s) may not be reflected by the strength—CSA relationship depending on the movements (such as hip adduction-adductor muscle CSA). Thus, further studies are required to develop methods to assess neuromuscular function in relation to muscle morphology among soccer players.  相似文献   

13.
Limb dominance theory suggests that females tend to be more one-leg dominant and exhibit greater kinematic and kinetic leg asymmetries than their male counterparts, contributing to the increased risk of anterior cruciate ligament injury among female athletes. Thus, the purpose of this study was to examine the influences of sex and limb dominance on lower extremity joint mechanics during unilateral land-and-cut manoeuvres. Twenty-one women and 21 men completed land-and-cut manoeuvres on their dominant limb as well as their nondominant limb. Three-dimensional kinematics and kinetics were calculated bilaterally for the entire stance phase of the manoeuvre. Women performed land-and-cut manoeuvres with altered hip motions and loads as well as greater knee abduction at touchdown compared to men. Dominant limb land-and-cut manoeuvres where characterised by decreased hip flexion at touchdown as well as decreased hip flexion and adduction range of motion compared to nondominant land-and-cuts regardless of sex. The observed sex differences are consistent with previous research regarding mechanisms underlying the sex disparity in anterior cruciate ligament injury rates. However, observed differences regarding limb dominances appear somewhat arbitrary and did not suggest that the dominant or nondominant limb would be at increased risk of anterior cruciate ligament injury.  相似文献   

14.
Turns (pirouettes) are an important movement in ballet and may be affected by “lateral bias”. This study investigated physiological differences exhibited by experienced and novice dancers, respectively, when performing pirouette with dominant and non-dominant leg supports, respectively. Thirteen novice and 13 experienced dancers performed turns on dominant or non-dominant legs. The maximum ankle plantarflexion, knee extension and hip extension were measured during the single-leg support phase. The inclination angle of rotation axis is the angle between instantaneous rotation axis and global vertical axis in the early single-leg support phase. Both groups exhibited a greater hip extension, knee extension, and ankle plantarflexion when performing a turn on the non-dominant leg. For experienced dancers, the inclination angle of rotation axis during the pre-swing phase was generally smaller for dominant leg support than non-dominant leg. However, no significant difference was found in inclination angle of rotation axis of novice dancers. For experienced dancers, an improved performance is obtained when using the dominant leg for support. By contrast, for novice dancers, the performance is independent of choice of support leg. The significant lateral bias in experienced dancers indicates the possible influence of training. That is, repetitive rehearsal on the preferred leg strengthens the impact of side dominance in experienced dancers.  相似文献   

15.
Sprinting while towing a sled improves sprinting parameters, however, only kinematic and temporal–spatial variables have been reported. The purpose of this study was to determine how lower extremity joint moment impulses alter when towing a sled compared to normal walking. Twelve participants walked normally, walked while towing a sled with a 50% body weight load attached at the waist, and with a 50% body weight load attached at the shoulders. Joint moment impulses were calculated for the hip, knee, and ankle. A mixed-model ANOVA with a between-subject factor of limb and repeated measures of condition was used to compare differences between limbs and towing conditions for each joint. Towing a sled increased joint moment impulses at the hip, knee, and non-dominant ankle. When compared with normal walking waist attachment increased hip extension moment impulse by 214.5% ( ? 3.31 vs. ? 10.41 Nms/kg), and shoulder attachment increased knee extension moment impulse by 166.9% (4.62 vs. 12.33 Nms/kg). The dominant limb produced greater knee extension moment impulse (p < 0.001), while the non-dominant limb produced greater hip extension (p < 0.001) and ankle plantarflexion moment impulse (p < 0.001) across all conditions. Results suggest that walking while towing may increase hip and knee extension strength.  相似文献   

16.
The purpose of this study is to examine the peak sagittal plane joint angles and joint moments of the lower extremity during the deep squat (DS) movement of the Functional Movement Screen (FMS) to assess differences between the classifications (1,2,3). Twenty-eight participants volunteered for the study and were screened to assess their FMS score on the DS task. All participants underwent a quantitative movement analysis performing the FMS DS movement at a self-selected speed. The participants in Group 3 exhibited greater dorsiflexion excursion compared to those in Group 1. Participants in Group 3 had greater peak knee flexion and knee flexion excursion than those in Group 2 who exhibited more than the participants in Group 1. Group 3 also exhibited a greater peak knee extension moment compared to Group 1. At the hip, Groups 3 and 2 exhibited greater peak hip flexion, hip flexion excursion and peak hip extension moment compared to Group 1. Thus, it appears that individuals who score differently on the deep squat as determined by the FMS exhibit differences in mechanics that may be beneficial in assessing strategies for interventions. Future research should assess how fundamental changes in mobility and stability independently affect DS performance.  相似文献   

17.
The purpose of this study is to examine the peak sagittal plane joint angles and joint moments of the lower extremity during the deep squat (DS) movement of the Functional Movement Screen (FMS) to assess differences between the classifications (1,2,3). Twenty-eight participants volunteered for the study and were screened to assess their FMS score on the DS task. All participants underwent a quantitative movement analysis performing the FMS DS movement at a self-selected speed. The participants in Group 3 exhibited greater dorsiflexion excursion compared to those in Group 1. Participants in Group 3 had greater peak knee flexion and knee flexion excursion than those in Group 2 who exhibited more than the participants in Group 1. Group 3 also exhibited a greater peak knee extension moment compared to Group 1. At the hip, Groups 3 and 2 exhibited greater peak hip flexion, hip flexion excursion and peak hip extension moment compared to Group 1. Thus, it appears that individuals who score differently on the deep squat as determined by the FMS exhibit differences in mechanics that may be beneficial in assessing strategies for interventions. Future research should assess how fundamental changes in mobility and stability independently affect DS performance.  相似文献   

18.
The purpose of the study was to determine if the kinematics exhibited by skilled runners wearing a unilateral, transtibial prosthesis during the curve section of a 200-m sprint race were influenced by interaction of limb-type (prosthetic limb (PROS-L) vs. nonprosthetic limb (NONPROS-L)) and curve-side (inside and outside limb relative to the centre of the curve). Step kinematics, toe clearance and knee and hip flexion/extension, hip ab/adduction for one stride of each limb were generated from video of 13 males running the curve during an international 200 m transtibial-classified competition. Using planned comparisons (P < 0.05), limb-type and curve-side interactions showed shortest support time and lowest hip abduction displacement by outside-NONPROS-L; shortest step length and longest time to peak knee flexion by the inside-PROS-L. For limb-type, greater maximum knee flexion angle and lower hip extension angles and displacement during support and toe clearance of PROS-Ls occurred. For curve-side, higher hip abduction angles during non-support were displayed by inside-limbs. Therefore, practitioners should consider that, for curve running, these kinematics are affected mostly by PROS-L limitations, with no clear advantage of having the PROS-L on either side of the curve.  相似文献   

19.
This study assessed muscular torque and rate of torque development following concentric (CON) or eccentric (ECC) isokinetic training. Thirty-eight women were randomly assigned to either CON or ECC training groups. Training consisted of knee extension and flexion of the nondominant leg three times per week for 20 weeks (SD = 1). Eccentric training increased ECC knee extension and flexion peak torque more than CON training. The ECC group improved acceleration time and time to peak torque with ECC movements versus the CON group. Slow-velocity ECC isokinetic training yielded greater ECC and similar CON torque development gains versus CON training over the course of 20 weeks in young women.  相似文献   

20.
Abstract

We aimed to illustrate support leg dynamics during instep kicking to evaluate the role of the support leg action in performance. Twelve male soccer players performed maximal instep kicks. Their motions and ground reaction forces were recorded by a motion capture system and a force platform. Moments and angular velocities of the support leg and pelvis were computed using inverse dynamics. In most joints of the support leg, the moments were not associated with or counteracting the joint motions except for the knee joint. It can be interpreted that the initial knee flexion motion counteracting the extension joint moment has a role to attenuate the shock of landing and the following knee extension motion associated with the extension joint moment indirectly contributes to accelerate the swing of kicking leg. Also, appreciable horizontal rotation of the pelvis coincided with increase of the interaction moment due to the hip joint reaction force on the support leg side. It can be assumed that the interaction moment was the main factor causing the pelvis counter-clockwise rotation within the horizontal plane from the overhead view that precedes a proximal-to-distal sequence of segmental action of the swing leg.  相似文献   

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