Could knee joint mechanics during the golf swing be contributing to chronic knee injuries in professional golfers?     

Howie Carson  Jim Richards  Simon G. S. Coleman 《Journal of sports sciences》2020,38(13):1575-1584

ABSTRACT

Full three-dimensional movements and external moments in golfers’ knees and the possible involvement in injuries have not been evaluated using motion capture at high sample frequencies. This study measured joint angles and external moments around the three anatomical axes in both knees of 10 professional golfers performing golf drives whilst standing on two force plates in a motion capture laboratory. Significant differences were found in the knee joint moments between the lead and trail limbs for the peak values and throughout all stages during the swing phase. A significantly higher net abduction moment impulse was seen in the trail limb compared with the lead limb (?0.518 vs. ?0.135 Nms.kg^?1), indicating greater loading over the whole swing, which could contribute to knee lateral compartment or anterior cruciate ligament injuries. A significant correlation (r = ?0.85) between clubhead speed at ball contact and maximum joint moment was found, with the largest correlations being found for joint moments at the top of the backswing event and at the end of the follow-through. Therefore, although knee moments can contribute to high clubhead speeds, the large moments and impulses suggest that they may also contribute to chronic knee injuries or exacerbate existing conditions.  相似文献   

运动生物力学方法在运动分析中的应用   总被引：6，自引：1，他引：5  

王新 《沈阳体育学院学报》2004,23(1):57-58

随着科学技术的不断发展,运用运动生物力学方法对运动进行分析的手段变得越来越先进。为了给进行体育研究的人员提供分析思路与研究方法,对国内外目前普遍使用的运动学、动力学及将二者结合的方法进行综合评述,探讨各种方法的优缺点,并发现目前我国虽然较多使用运动学和动力学进行分析,但将两者结合起来进行分析者较少,就此提出将两种方法结合起来对运动项目进行分析的设想与思路,即通过等动测试获得做功关节处的肌力矩大小,并利用录像解析获得做功环节的运动学数据———角速度,将两者结合来分析功率输出情况。  相似文献   

青少年男子铅球运动员施力特征探析     

张庆来  薛存波  葛超 《辽宁体育科技》2006,28(4):18-19

采用三维数字测力铅球仪对青少年运动员在整个投掷过程中的施力特征与动作技术特征进行分析,结果表明:(1)在完整推铅球动作过程中运动员对铅球的作用力曲线与铅球速度变化趋势基本一致,在最后用力动作过程中,合力曲线呈“双峰型”;(2)在最后用力开始左脚着地瞬间力值逐渐增大,到右腿蹬转使运动员身体由侧对投掷方向转为正对投掷方向瞬间出现第一次峰值;在推掷臂肘关节夹角约为90°时出现第二次峰值。  相似文献   

Influence of sex and limb dominance on lower extremity joint mechanics during unilateral land-and-cut manoeuvres     

Joshua T. Weinhandl  Bobbie S. Irmischer  Zachary A. Sievert  Kevin C. Fontenot 《Journal of sports sciences》2017,35(2):166-174

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   

影响男子排球运动员扣球起跳动作效果的 动力学研究          下载免费PDF全文

贾谊 《河北体育学院学报》2017,31(5):64-70

目的:研究男子排球运动员扣球起跳蹬地动作过程中,人体下肢的相关力学参数特征.对象:男子大学生排球运动员10名.方法:使用高速人体动作捕捉系统及三维测力台,对相关运动学和动力学参数进行采集.结果:①起跳过程中,地面反作用力峰值和均值均为优势腿大于非优势腿;②非优势腿地面反作用力峰值与重心最大高度呈高度负相关(r=-0.961,P=0.002＜0.05);③双脚同时着地过程中,优势腿地面反作用力冲量明显大于非优势腿,两脚地面反作用力冲量差与重心最大高度呈显著负相关(r=-0.531,P=0.034＜0.05).结论:①在后排起跳过程中,优势腿与非优势腿表现出不同的用力形式;②应当通过适当控制非优势腿在着地初期的制动作用,并在双脚最后用力阶段有意识地提高非优势腿的参与程度,以提高人体的起跳高度;③排球运动员髌腱炎的发病可能与踝关节绕矢状轴力矩和膝关节绕垂直轴力矩较大有关.  相似文献   

Differences in pedalling technique between road cyclists of different competitive levels     

Juan García-López  Sergio Díez-Leal  Ana Ogueta-Alday  Josu Larrazabal  José A. Rodríguez-Marroyo 《Journal of sports sciences》2016,34(17):1619-1626

The purpose of this study was to compare the pedalling technique in road cyclists of different competitive levels. Eleven professional, thirteen elite and fourteen club cyclists were assessed at the beginning of their competition season. Cyclists’ anthropometric characteristics and bike measurements were recorded. Three sets of pedalling (200, 250 and 300 W) on a cycle ergometer that simulated their habitual cycling posture were performed at a constant cadence (~90 rpm), while kinetic and kinematic variables were registered. The results showed no differences on the main anthropometric variables and bike measurements. Professional cyclists obtained higher positive impulse proportion (1.5–3.3% and P < 0.05), mainly due to a lower resistive torque during the upstroke (15.4–28.7% and P < 0.05). They also showed a higher ankle range of movement (ROM, 1.1–4.0° and P < 0.05). Significant correlations (P < 0.05) were found between the cyclists’ body mass and the kinetic variables of pedalling: positive impulse proportion (r = ?0.59 to ?0.61), minimum (r = ?0.59 to ?0.63) and maximum torques (r = 0.35–0.47). In conclusion, professional cyclists had better pedalling technique than elite and club cyclists, because they opted for enhancing pulling force at the recovery phase to sustain the same power output. This technique depended on cycling experience and level of expertise.  相似文献   

Ankle and knee kinetics between strike patterns at common training speeds in competitive male runners     

Daniel Kuhman  Daniel Melcher 《European Journal of Sport Science》2016,16(4):433-440

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   

Ground reaction forces of Olympic and World Championship race walkers     

Brian Hanley  Athanassios Bissas 《European Journal of Sport Science》2016,16(1):50-56

Race walking is an Olympic event where no visible loss of contact should occur and the knee must be straightened until midstance. The purpose of this study was to analyse ground reaction forces of world-class race walkers and associate them with key spatiotemporal variables. Nineteen athletes race walked along an indoor track and made contact with two force plates (1000 Hz) while being filmed using high-speed videography (100 Hz). Race walking speed was correlated with flight time (r = .46, p = .049) and flight distance (r = .69, p = .001). The knee's movement from hyperextension to flexion during late stance meant the vertical push-off force that followed midstance was smaller than the earlier loading peak (p < .001), resulting in a flattened profile. Athletes with narrower stride widths experienced reduced peak braking forces (r = .49, p = .046), peak propulsive forces (r = .54, p = .027), peak medial forces (r = .63, p = .007) and peak vertical push-off forces (r = .60, p = .011). Lower fluctuations in speed during stance were associated with higher stride frequencies (r = .69, p = .001), and highlighted the importance of avoiding too much braking in early stance. The flattened trajectory and consequential decrease in vertical propulsion might help the race walker avoid visible loss of contact (although non-visible flight times were useful in increasing stride length), while a narrow stride width was important in reducing peak forces in all three directions and could improve movement efficiency.  相似文献   

有机合成反应选择性及其控制策略     

李文辉 《荆门职业技术学院学报》2007,22(3):90-96

有机合成是化学研究领域中最具有魅力的。结构复杂、性质多元、应用广泛的有机物及其合成方法学,让人赞叹与探求。文章用科学方法论总结了有机合成中的化学选择性、区域选择性和立体选择性的规律及其热力学和动力学控制策略,提出了综合利用其控制原理解释或预测竞争性反应产物的基本方法。  相似文献   

Hydrogenation properties of mechanically milled Mg2Nio.8Cr0.2-CoO/Al2O3 composites     

WANG Xiu-li  TU Jiang-ping  CHEN Chang-pin  ZHANG Xiao-bin  ZHAO Xin-bing 《Journal of Zhejiang University. Science. B》2005,(3)

Mg2Ni0.8Cr0.2-x wt.% CoO/Al2O3 (x=0.5, 1, 2 and 3) composites were prepared by mechanically milling sintered Mg2Ni0.8Cr0.2 alloy and CoO/Al2O3 compound for 45 h. The addition of CoO/Al2O3 compound resulted in the good kinetics properties of hydriding/dehydriding reaction of the composites. The composite with 1.0 wt.% CoO/Al2O3 catalyst could reach the maximum hydrogen absorption capacity (2.9 wt.%) within 5 min at 393 K under H2 pressure of 4 MPa, and can desorb rapidly at 493 K. The decomposition and synthesis of hydrogen molecule on Mg2Ni0.8Cr0.2 alloy surface was promoted by addition of CoO/Al2O3 catalyst. In addition, the formation of metallic Ni particles, strain and defects during the ball milling process also resulted in the improved hydrogenation performance of Mg2Ni-based alloys.  相似文献