Effects and mechanisms of different exercise modalities on inflammation in older adults, particularly with sarcopenia: a narrative review.

Sarcopenia is a prevalent age-related muscle disorder characterized by progressive loss of muscle mass and function, and chronic low-grade inflammation ("inflammaging(definition)") is recognized as a key contributor to its pathogenesis. Exercise has been proposed as an effective non-pharmacological strategy to counteract inflammation and improve muscle health; however, the anti-inflammatory effects and underlying mechanisms of different exercise modalities remain incompletely understood. This review aims to summarize and compare the effects of different exercise modalities on inflammatory responses in older adults with sarcopenia and to elucidate the potential molecular and cellular mechanisms involved. A narrative review was conducted by searching PubMed, Web of Science, and Scopus for relevant studies published in the past decade. Clinical trials and experimental studies investigating aerobic exercise, resistance training, high-intensity interval training, and combined training interventions in older adults with sarcopenia were included. Outcomes of interest focused on systemic and muscle-derived inflammatory markers, including tumor necrosis factor-α, interleukin-6, C-reactive protein, and anti-inflammatory cytokines. Aerobic exercise predominantly reduces systemic inflammatory markers and improves metabolic regulation, whereas resistance training mainly attenuates muscle-derived inflammatory signaling and promotes anabolic responses. High-intensity interval training and combined training programs appear to exert complementary effects on both systemic and local inflammation. At the molecular level, exercise-induced anti-inflammatory effects are associated with suppression of pro-inflammatory pathways such as nuclear factor-κB and toll-like receptor 4, and activation of regulatory pathways including AMP-activated protein kinase/sirtuin 1 and nuclear factor erythroid 2-related factor 2. In addition, exercise modulates myokine secretion and immune cell phenotypes, contributing to an improved inflammatory microenvironment in skeletal muscle. Different exercise modalities exert distinct but overlapping anti-inflammatory effects in older adults with sarcopenia. Understanding the specific inflammatory targets and mechanisms of various exercise interventions may facilitate the development of individualized and optimized exercise prescriptions for the prevention and management of sarcopenia.