A BIOMECHANICAL ANALYSIS OF MUSCLE STRENGTH AS A LIMITING FACTOR IN STANDING POSTURE
A BIOMECHANICAL ANALYSIS OF MUSCLE STRENGTH AS A LIMITING FACTOR IN STANDING POSTURE
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DOI：
10.1016/0021-9290(93)90085-s
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发表时间：
1993-01-01
影响因子：
2.4
通讯作者：
ZAJAC, FE
中科院分区：
文献类型：
--
作者：
KUO, AD;ZAJAC, FE
我们开发了一种研究多关节运动中肌肉协调性和力量的方法，并将其应用于站立姿势。该方法基于人体下肢在矢状面上的肌肉骨骼模型，以及一种从几何上可视化身体内外约束如何影响运动的技术。我们开发了一种算法来计算肌肉可以诱导的所有可行加速度的集合(即‘可行加速度集’，或FAS)。对于矢状面中的踝关节、膝盖和髋关节，该集是三维中的多面体。使用Fas的体积作为整体活动度的指标，我们发现加强身体后侧(而不是前侧)的肌肉将导致更大的活动度增加。利用其他人的实验观察，我们还发现，加速度约束大大缩小了可行加速度的范围。然后我们定义了一组四个基本的加速度向量，当它们在各种组合中使用时，可以产生姿势动作的曲目。我们使用线性规划来找出这些向量的最大幅度，以及这些幅度对肌肉力量的敏感度，从而描绘出那些肌肉，如果加强，将导致身体产生基本加速度向量的能力最大的增加。在我们的特殊模型中，这些肌肉群被发现是腿肌、胫骨前肌、股直肌和腓肠肌。这些肌肉群在肌肉力量严重下降的情况下非常重要。因此，这种方法可能对设计功能性电刺激控制器或在FISK进行跌倒练习等目的很有用。
We developed a method for studying muscular coordination and strength in multijoint movements and have applied it to standing posture. The method is based on a musculoskeletal model of the human lower extremity in the sagittal plane and a technique to visualize, geometrically, how constraints internal and external to the body affect movement. We developed an algorithm to calculate the set of all feasible accelerations (i.e., the 'feasible acceleration set', or FAS) that muscles can induce. For the ankle, knee, and hip joints in the sagittal plane, this set is a polyhedron in three dimensions. Using the volume of the FAS as an indicator of overall mobility, we found that strengthening muscles on the posterior side (as opposed to the anterior) of the body would cause greater increases in mobility. Employing the experimental observations of others, we also found that acceleration constraints greatly reduce the range of feasible accelerations. We then defined a set of four basic acceleration vectors which, when used in various combinations, can produce the repertoire of postural movements. We used linear programming to find the maximum magnitudes of these vectors, and the sensitivity of these magnitudes to muscle strength, thereby delineating those muscles which, if strengthened, would cause the greatest increase in the body's ability to generate the basic acceleration vectors. For our particular model, those muscle groups were found to be hamstrings, tibialis anterior, rectus femoris, and gastrocnemius. These Muscle groups would be of great importance in cases involving severely reduced muscle strength. This methodology may therefore be useful for purposes such as design of functional electrical stimulation controllers or exercises for persons at fisk for falling.