Escamilla R F, Fleisig G S, Lowry T M, Barrentine S W, Andrews J R
Michael W. Krzyzewski Human Performance Laboratory, Division of Orthopaedic Surgery, Duke University Medical Center, Durham, NC 27710, USA.
Med Sci Sports Exerc. 2001 Jun;33(6):984-98. doi: 10.1097/00005768-200106000-00019.
The purpose of this study was to quantify biomechanical parameters employing two-dimensional (2-D) and three-dimensional (3-D) analyses while performing the squat with varying stance widths.
Two 60-Hz cameras recorded 39 lifters during a national powerlifting championship. Stance width was normalized by shoulder width (SW), and three stance groups were defined: 1) narrow stance squat (NS), 107 +/- 10% SW; 2) medium stance squat (MS), 142 +/- 12% SW; and 3) wide stance squat (WS), 169 +/- 12% SW.
Most biomechanical differences among the three stance groups and between 2-D and 3-D analyses occurred between the NS and WS. Compared with the NS at 45 degrees and 90 degrees knee flexion angle (KF), the hips flexed 6-11 degrees more and the thighs were 7-12 degrees more horizontal during the MS and WS. Compared with the NS at 90 degrees and maximum KF, the shanks were 5-9 degrees more vertical and the feet were turned out 6 degrees more during the WS. No significant differences occurred in trunk positions. Hip and thigh angles were 3-13 degrees less in 2-D compared with 3-D analyses. Ankle plantar flexor (10-51 N.m), knee extensor (359-573 N.m), and hip extensor (275-577 N.m) net muscle moments were generated for the NS, whereas ankle dorsiflexor (34-284 N.m), knee extensor (447-756 N.m), and hip extensor (382-628 N.m) net muscle moments were generated for the MS and WS. Significant differences in ankle and knee moment arms between 2-D and 3-D analyses were 7-9 cm during the NS, 12-14 cm during the MS, and 16-18 cm during the WS.
Ankle plantar flexor net muscle moments were generated during the NS, ankle dorsiflexor net muscle moments were produced during the MS and WS, and knee and hip moments were greater during the WS compared with the NS. A 3-D biomechanical analysis of the squat is more accurate than a 2-D biomechanical analysis, especially during the WS.
本研究的目的是在进行不同站立宽度的深蹲时，采用二维（2-D）和三维（3-D）分析来量化生物力学参数。
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39名举重运动员的情况。站立宽度通过肩宽（SW）进行标准化，并定义了三个站立组：1）窄站距深蹲（NS），107±10%SW；2）中站距深蹲（MS），142±12%SW；3）宽站距深蹲（WS），169±12%SW。
三个站立组之间以及二维和三维分析之间的大多数生物力学差异出现在NS和WS之间。在45度和90度膝关节屈曲角度（KF）时，与NS相比，MS和WS期间髋关节多屈曲6 - 11度，大腿多水平7 - 12度。在90度和最大KF时，与NS相比，WS期间小腿多垂直5 - 9度，双脚外旋多6度。躯干位置没有显著差异。与三维分析相比，二维分析中的髋关节和大腿角度小3 - 13度。NS期间，踝关节跖屈肌（10 - 51 N·m）、膝关节伸肌（359 - 573 N·m）和髋关节伸肌（275 - 577 N·m）产生净肌肉力矩，而MS和WS期间，踝关节背屈肌（34 - 284 N·m）、膝关节伸肌（447 - 756 N·m）和髋关节伸肌（382 - 628 N·m）产生净肌肉力矩。二维和三维分析之间，踝关节和膝关节力臂的显著差异在NS期间为7 - 9厘米，MS期间为12 - 14厘米，WS期间为16 - 18厘米。
NS期间产生踝关节跖屈肌净肌肉力矩，MS和WS期间产生踝关节背屈肌净肌肉力矩，与NS相比，WS期间膝关节和髋关节力矩更大。深蹲的三维生物力学分析比二维生物力学分析更准确，尤其是在WS期间。
