Biomedical Engineering Graduate Program, Schulich School of Engineering, University of Calgary, 2500 University Drive NW, Calgary, AB T2N 1N4, Canada.
Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, 2500 University Drive NW, Calgary, AB T2N 1N4, Canada.
Sensors (Basel). 2021 Oct 28;21(21):7145. doi: 10.3390/s21217145.
Human movement patterns were shown to be as unique to individuals as their fingerprints. However, some movement characteristics are more important than other characteristics for machine learning algorithms to distinguish between individuals. Here, we explored the idea that movement patterns contain unique characteristics that differentiate between individuals and generic characteristics that do not differentiate between individuals. Layer-wise relevance propagation was applied to an artificial neural network that was trained to recognize 20 male triathletes based on their respective movement patterns to derive characteristics of high/low importance for human recognition. The similarity between movement patterns that were defined exclusively through characteristics of high/low importance was then evaluated for all participants in a pairwise fashion. We found that movement patterns of triathletes overlapped minimally when they were defined by variables that were very important for a neural network to distinguish between individuals. The movement patterns overlapped substantially when defined through less important characteristics. We concluded that the unique movement characteristics of elite runners were predominantly sagittal plane movements of the spine and lower extremities during mid-stance and mid-swing, while the generic movement characteristics were sagittal plane movements of the spine during early and late stance.
人类的运动模式与指纹一样具有个体独特性。然而，对于机器学习算法来说，某些运动特征比其他特征更重要，可以用来区分个体。在这里，我们探讨了这样一种观点，即运动模式包含了可以区分个体的独特特征和不能区分个体的通用特征。分层相关性传播被应用于一个人工神经网络，该网络经过训练，可以根据各自的运动模式识别 20 名男性铁人三项运动员，从而得出对人类识别具有高/低重要性的特征。然后，以成对的方式评估所有参与者的运动模式之间基于高/低重要性特征定义的相似性。我们发现，当根据对神经网络区分个体非常重要的变量定义运动模式时，运动员的运动模式重叠最小。当通过不太重要的特征定义时，运动模式会发生很大的重叠。我们的结论是，精英跑步者独特的运动特征主要是中驻和中摆阶段脊柱和下肢的矢状面运动，而通用的运动特征是早期和晚期驻留阶段脊柱的矢状面运动。
