Exercise, Exerkines, and Sarcopenia

Sarcopenia is a progressive age-related musculoskeletal disorder characterized by loss of skeletal muscle mass, strength, and physical function. Closely associated with aging and physical inactivity, it significantly compromises mobility, independence, and quality of life in older adults. Exercise is widely recognized as an effective non-pharmacological intervention for managing sarcopenia. However, the underlying molecular mechanisms remain incompletely elucidated. Among the emerging mediators, exerkines, physical exercise-induced signaling molecules, are secreted by multiple tissues, including the skeletal muscle, bone, liver, and adipose tissue, and mediate the systemic beneficial impacts of exercise via autocrine, paracrine, and endocrine signaling. These factors play critical roles in interorgan communication, regulation of muscle regeneration, mitochondrial function, inflammation, and metabolic homeostasis. Importantly, the secretion profiles and biological functions of exerkines are modulated by exercise-specific parameters such as mode, intensity, and duration. Understanding the regulatory dynamics of exerkine signaling may offer novel therapeutic avenues, particularly for individuals unable to engage in regular physical activity. This review focuses on the recently identified exerkines relevant to skeletal muscle physiology and their implications in the pathophysiology of sarcopenia. We also provided a comprehensive overview of exerkine responses to various exercise modalities in the prevention and treatment of sarcopenia.