Muscle architecture, which includes parameters like fascicle length, pennation angle, and physiological cross-sectional area, strongly influences skeletal muscles' mechanical properties. During maturation, the muscle architecture has to adapt to a growing organism. This study aimed to develop an architectural model capable of predicting the complete 3D fascicle architecture for primarily unipennate muscles of an arbitrary age, based on fascicle data for an initial age. For model development, we collected novel data on 3D muscle architecture of the rabbit (Oryctolagus cuniculus) M. plantaris of eight animals ranging in age from 29 to 106 days. Experimental results show that plantaris muscle belly length increases by 73%, whereas mean fascicle length and mean pennation angle increases by 39 and 14%, respectively. Those changes were incorporated into the model. In addition to the data collected for M. plantaris the predictions of the model were compared to existing literature data of rabbit M. soleus and M. gastrocnemius medialis. With an error of −1.0 ± 8.6% for relative differences in aponeurosis length, aponeurosis width, muscle height, and muscle mass, the model delivered good results matching interindividual differences. For future studies, the model could be utilized to generate realistic architectural data sets for simulation studies.

肌肉结构，包括束长度、羽状角和生理横截面积等参数，强烈影响骨骼肌的力学性能。在成熟过程中，肌肉结构必须适应不断增长的有机体。本研究旨在开发一种架构模型，该模型能够基于初始年龄的肌束数据预测任意年龄的主要单肌束的完整 3D 肌束结构。对于模型开发，我们收集了 8 只年龄从 29 到 106 天的动物的3D肌肉结构的新数据。实验结果表明，跖肌腹长度增加了 73%，而平均肌束长度和平均羽状角分别增加了 39% 和 14%。这些变化被纳入模型。除了为足底分枝杆菌收集的数据外，还将模型的预测与兔比目鱼分枝杆菌和腓肠肌内侧肌的现有文献数据进行了比较。对于腱膜长度、腱膜宽度、肌肉高度和肌肉质量的相对差异，该模型的误差为 -1.0 ± 8.6%，该模型提供了与个体间差异匹配的良好结果。对于未来的研究，该模型可用于为模拟研究生成逼真的建筑数据集。