Takei Yoshiaki
Department of Kinesiology and Physical Education, Northern Illinois University, DeKalb, IL 60115-2854, USA.
J Appl Biomech. 2007 Feb;23(1):1-11. doi: 10.1123/jab.23.1.1.
The purpose of the study was to determine the mechanical variables that are related to successful post-flight somersaulting performance of the Roche vault. The 23 Roche vaults performed during the 2000 Olympic Games were filmed by a 16-mm camera operating at 100 Hz. The 2-D direct linear transformation technique was used for spatial calibration. Approximately 60 frames were digitized per vault. The method of Hay and Reid (1988) was used to develop a deterministic model to identify the mechanical variables that govern linear and angular motions of the vault. Correlational analysis was used to establish the strength of the relationship between the mechanical variables identified and the judges' scores. Significant correlations indicated that the higher judges' scores were negatively related to five mechanical variables and positively related to seventeen variables in the model. The normalized horizontal displacement of body center of mass (CM) from the knee grasp to the peak of post-flight was the best single predictor of the judges' score and accounted for 50% of variation in the judges' score. Finally, the landing point deductions and the official horizontal distance of post-flight collectively accounted for 86% of the variance in the judges' scores.
该研究的目的是确定与罗氏跳马飞行后成功完成翻筋斗动作相关的力学变量。在2000年奥运会期间进行的23次罗氏跳马动作,由一台以100赫兹运行的16毫米摄像机进行拍摄。采用二维直接线性变换技术进行空间校准。每次跳马大约有60帧被数字化。使用Hay和Reid(1988年)的方法建立一个确定性模型,以识别控制跳马线性和角向运动的力学变量。采用相关分析来确定所识别的力学变量与裁判评分之间关系的强度。显著相关性表明,裁判的高分与模型中的五个力学变量呈负相关,与十七个变量呈正相关。从抓膝到飞行后最高点身体重心(CM)的归一化水平位移是裁判评分的最佳单一预测指标,占裁判评分变化的50%。最后,着陆点扣分和飞行后的官方水平距离共同占裁判评分方差的86%。