We present and evaluate a new approach to estimate calf muscle-tendon parameters and calculate calf muscle-tendon function during walking. We used motion analysis, ultrasound, and EMG data of the calf muscles collected in six young and six older adults during treadmill walking as inputs to a new optimal estimation algorithm. We used estimated parameters or scaled generic parameters in an existing approach to calculate muscle fiber lengths and activations. We calculated the fit with experimental data in terms of root mean squared differences (RMSD) and coefficients of determination (R2). We also calculated the calf muscle metabolic energy cost. RMSD between measured and calculated fiber lengths and activations decreased and R2 increased when estimating parameters compared to using scaled generic parameters. Moreover, R2 between measured and calculated gastrocnemius medialis fiber length and soleus activations increased by 19 and 70%, and calf muscle metabolic energy decreased by 25% when using estimated parameters compared to using scaled generic parameters at speeds not used for estimation. This new approach estimates calf muscle-tendon parameters in good accordance with values reported in literature. The approach improves calculations of calf muscle-tendon interaction during walking and highlights the importance of individualizing calf muscle-tendon parameters.

中文翻译：

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基于超声的最佳参数估计改进了行走过程中小腿肌肉-腱相互作用的评估。

我们提出并评估一种新的方法来估计小腿肌腱参数并计算步行过程中的小腿肌腱功能。我们使用运动分析，超声和肌电数据对跑步机行走过程中在六个年轻人和六个老年人中采集的小腿肌肉进行了分析，以此作为新的最佳估算算法的输入。在现有方法中，我们使用估计参数或按比例缩放的通用参数来计算肌肉纤维长度和激活。我们根据均方根差（RMSD）和确定系数（R2）计算了与实验数据的拟合度。我们还计算了小腿肌肉的代谢能量消耗。与使用比例缩放的通用参数相比，估算参数时，测量和计算的光纤长度与激活之间的RMSD降低，R2增加。此外，与未使用估算速度的比例通用参数相比，使用估算参数时，测量和计算的腓肠肌内侧纤维长度和比目鱼肌激活之间的R2分别增加了19％和70％，小腿肌肉的代谢能量减少了25％。这种新方法可以很好地估计小腿肌肉腱参数，与文献报道的值一致。该方法改进了行走过程中小腿肌肉-肌腱相互作用的计算，并强调了个体化小腿肌肉-肌腱参数的重要性。这种新方法可以很好地估计小腿肌肉腱参数，与文献报道的值一致。该方法改进了行走过程中小腿肌肉-肌腱相互作用的计算，并强调了个体化小腿肌肉-肌腱参数的重要性。这种新方法可以很好地估计小腿肌腱参数，与文献报道的值一致。该方法改进了步行过程中小腿肌肉-肌腱相互作用的计算，并强调了个体化小腿肌肉-肌腱参数的重要性。