The first part of this talk will present our recent discovery in muscle stem cell senescence and its role in muscle regeneration. Our daily movement and physical activity entirely rely on skeletal muscle. Paradoxically, extreme physical activity exposes to a chance of muscle injury. The skeletal muscle, which often suffers from exercise-induced damage, has self-healing capacity. Muscle repair comprises several processes, including the activation and proliferation of quiescent resident muscle stem cells, also known as satellite cells. The diminished pool of muscle stem cells and their renewal ability are the major driving forces of muscle aging. Here, we show that acute muscle injury could trigger the senescence of muscle stem cells. However, we could find the sign of cellular senescence in the naturally aged muscle in mice. The second part will briefly show a machine learning-based prediction of biomarkers for muscle aging diseases, including sarcopenia and myositis.