DeepSarcAE: A Deep Autoencoder Framework for Learning Gait Dynamics in the Detection of Sarcopenia

Sarcopenia is a degenerative musculoskeletal condition recognised as the age-related decline in skeletal muscle mass, strength, and function. Traditional diagnostic methods are limited by cost, accessibility, and subjectivity. This study aimed to develop a non-invasive, AI-driven, video-based framework for early Sarcopenia detection using functional movement analysis. Participants with and without Sarcopenia were recorded performing functional movements such as level walking, stair climbing, and ramp walking. Ten representative frames were extracted from each participant, resulting in 300 images (150 Sarcopenic, 150 non-Sarcopenic) utilised for the study. The DeepSarcAE model is an integrated framework of an autoencoder and a CNN-based classifier. Its performance was benchmarked against pretrained architectures such as EfficientNet, ResNet, MobileNet, Inception, VGG16 and four custom CNN models. Evaluation metrics such as sensitivity, specificity, precision, negative predictive value (NPV), accuracy, and AUC were used to analyse the models. DeepSarcAE outperformed all other models, attaining 100% sensitivity, 83.33% specificity, 85.71% precision, 100% NPV, 91.67% accuracy, and an AUC of 0.96. VGG16 and MobileNet followed the performance of DeepSarcAE closely, while the Inception network exhibited the weakest results due to poor generalisation. TheDeepSarcAE framework offers a scalable, cost-effective, and non-invasive approach for Sarcopenia screening from the input gait image frames. Its promising preliminary performance highlights the potential of deep learning in early diagnosis and clinical decision support in preventive healthcare.