Escamilla R F, Francisco A C, Fleisig G S, Barrentine S W, Welch C M, Kayes A V, Speer K P, Andrews J R
Division of Orthopaedic Surgery, Duke University Medical Center, Durham, NC 27710, USA.
Med Sci Sports Exerc. 2000 Jul;32(7):1265-75. doi: 10.1097/00005768-200007000-00013.
Strength athletes often employ the deadlift in their training or rehabilitation regimens. The purpose of this study was to quantify kinematic and kinetic parameters by employing a three-dimensional analysis during sumo and conventional style deadlifts.
Two 60-Hz video cameras recorded 12 sumo and 12 conventional style lifters during a national powerlifting championship. Parameters were quantified at barbell liftoff (LO), at the instant the barbell passed the knees (KP), and at lift completion. Unpaired t-tests (P < 0.05) were used to compare all parameters.
At LO and KP, thigh position was 11-16 degrees more horizontal for the sumo group, whereas the knees and hips extended approximately 12 degrees more for the conventional group. The sumo group had 5-10 degrees greater vertical trunk and thigh positions, employed a wider stance (70 +/- 11 cm vs 32 +/- 8 cm), turned their feet out more (42 +/- 8 vs 14 +/- 6 degrees). and gripped the bar with their hands closer together (47 +/- 4 cm vs 55 +/- 10 cm). Vertical bar distance, mechanical work, and predicted energy expenditure were approximately 25-40% greater in the conventional group. Hip extensor, knee extensor, and ankle dorsiflexor moments were generated for the sumo group, whereas hip extensor, knee extensor, knee flexor, and ankle plantar flexor moments were generated for the conventional group. Ankle and knee moments and moment arms were significantly different between the sumo and conventional groups, whereas hip moments and moments arms did not show any significantly differences. Three-dimensional calculations were more accurate and significantly different than two-dimensional calculations, especially for the sumo deadlift.
Biomechanical differences between sumo and conventional deadlifts result from technique variations between these exercises. Understanding these differences will aid the strength coach or rehabilitation specialist in determining which deadlift style an athlete or patient should employ.
力量型运动员常在训练或康复方案中采用硬拉动作。本研究的目的是通过在相扑式和传统式硬拉过程中进行三维分析来量化运动学和动力学参数。
在一次全国力量举锦标赛期间，两台60赫兹的摄像机记录了12名相扑式和12名传统式硬拉运动员的动作。在杠铃离地（LO）、杠铃经过膝盖瞬间（KP）以及完成举重时对参数进行量化。采用非配对t检验（P < 0.05）比较所有参数。
在LO和KP时，相扑组大腿位置比传统组水平约高11 - 16度，而传统组膝盖和髋部伸展角度约比相扑组大12度。相扑组垂直躯干和大腿位置高5 - 10度，采用更宽的站姿（70±11厘米对32±8厘米），双脚外展角度更大（42±8对14±6度），双手抓握杠铃距离更近（47±4厘米对55±10厘米）。传统组垂直杠铃距离、机械功和预测能量消耗大约高25 - 40%。相扑组产生髋伸肌、膝伸肌和踝背屈肌力矩，而传统组产生髋伸肌、膝伸肌、膝屈肌和踝跖屈肌力矩。相扑组和传统组之间踝和膝力矩及力臂有显著差异，而髋力矩和力臂无显著差异。三维计算比二维计算更准确且差异显著，尤其是对于相扑式硬拉。
相扑式和传统式硬拉之间的生物力学差异源于这些动作技术的变化。了解这些差异将有助于力量教练或康复专家确定运动员或患者应采用哪种硬拉方式。
