Rejman Marek, Ochmann Bartosz
University School of Physical Education, Wroclaw, Poland.
J Appl Biomech. 2009 Nov;25(4):340-50. doi: 10.1123/jab.25.4.340.
The aim of this study was to develop a functional model of monofin swimming by assigning numerical forms to certain technique parameters. The precise determination of optimal foot displacement and monofin strain points toward a model aspect for increasing swimming speed. Eleven professional swimmers were filmed underwater. The kinematic data were then used as entry variable for an artificial neural network, which itself created the foundation for a model of monofin swimming technique. The resulting network response graphs indicate a division set of standard deviation values in which the examined angular parameters of foot and monofin displacement achieve optimal values in terms of gaining maximal swimming speed. During the upward movement, it is essential to limit dorsal foot flexion (-20) from the parallel position toward the shin (180 degrees). During the downward movement, plantar flexion should not exceed 180 degrees. The optimal scope of the proximal part of the fin strain is 35 degrees in the downward move ment and (-)27 degrees in the upward; the angles of attack of the distal part of the fin and its entire surface are limited to 37 degrees in the downward movement and (-)26 degrees in the upward. Optimization criteria allowed for movement modification to gain and maintain maximal velocity during both cycle phases and to limit cycle velocity decrease.
本研究的目的是通过为某些技术参数赋予数值形式来建立一个单鳍游泳的功能模型。精确确定最佳足部位移和单鳍应变点有助于构建一个提高游泳速度的模型。对11名专业游泳运动员进行了水下拍摄。运动学数据随后被用作人工神经网络的输入变量，该网络本身为单鳍游泳技术模型奠定了基础。生成的网络响应图显示了一组标准差数值，其中所研究的足部和单鳍位移角度参数在获得最大游泳速度方面达到了最佳值。在向上运动时，必须将足部背屈从平行位置向胫骨方向（180度）限制在-20度。在向下运动时，跖屈不应超过180度。鳍应变近端部分的最佳范围在向下运动时为35度，向上运动时为-27度；鳍远端部分及其整个表面的攻角在向下运动时限制在37度，向上运动时限制在-26度。优化标准允许对运动进行调整，以便在两个周期阶段获得并保持最大速度，并限制周期速度下降。
