Back lift versus leg lift: an index and visualization of dynamic lifting strategies.
Back lift versus leg lift: an index and visualization of dynamic lifting strategies.
复制标题
背部举升与腿部举升：动态举升策略的索引和可视化。
DOI：
10.1016/s0021-9290(00)00015-4
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发表时间：
2000
影响因子：
2.4
通讯作者：
Don B. Chaffin
中科院分区：
文献类型：
--
作者：
Xudong Zhang;M. Nussbaum;Don B. Chaffin
对提升策略的描述通常以定性的方式提供。定量静态描述符或索引区分起始姿势，但不区分主要的运动段。本技术说明提出了一个指数，定量表征在矢状面提升过程中采用的不同动态姿势策略。动态提升策略在速度域中建模为躯干和腿段之间的姿势变化分区的不同方案。该指数由两个参数组成，分配给两个腿段，量化它们相对于躯干的贡献。给定测量的升降运动，通过枚举搜索过程估计其指标参数值，范围为0.1至10，目标是最小化拟合误差。通过将该指数应用于6名受试者进行的24个举重动作来说明该指数的使用，这些受试者要么采用背举，要么采用腿举策略。结果表明，在腿部或背部通常是原动机方面，可以使用这个简单的双参数指标来区分和可视化举重策略。此外，模糊的中间策略也被辨别出来，因为在举重运动中每个部分的参与是量化的。然而，该指数是有限的，因为它不考虑手臂运动对提升的贡献，也不考虑在提升过程中可能的随时间变化的策略。潜在的未来应用包括时间效率运动预测和模拟计算机生物力学或人体工程学分析。
The description of a lifting strategy is typically provided in qualitative terms. A quantitative static descriptor or index differentiates the starting postures but not the primary moving segments. This technical note proposes an index that quantitatively characterizes different dynamic postural strategies employed during sagittal plane lifting. Dynamic lifting strategies are modeled in the velocity domain as different schemes of partitioning postural changes between the torso and leg segments. The index consists of two parameters, assigned to two leg segments, quantifying their contributions relative to the torso. Given a measured lifting movement, its index parameters values, ranging from 0.1 to 10, are estimated through an enumeration search process with the objective of minimizing the fitting error. The use of this index is illustrated by applying it to 24 lifting movements performed by six subjects assuming either a back-lift or a leg-lift strategy. Results indicate that a lifting strategy, in terms of whether the leg or the back is generally the prime mover, can be differentiated and visualized using this simple two-parameter index. In addition, indistinct intermediate strategies are also discerned, as the involvement of each segment in a lifting movement is quantified. The index is however limited in that it does not accommodate arm motion contributions to a lift nor possible time-dependent strategic changes during a lift. Potential future applications include time-efficient movement prediction and simulation for computerized biomechanical or ergonomic analysis.