Exercise slows immune ageing via multiple pathways
Your immune system ages. It becomes slower, chronically inflamed, and less effective at fighting infection and cancer.
Two phenomena define immune ageing. The first is inflammaging: a persistent, low-grade inflammation that gradually damages blood vessels, the brain, and organs. The second is immunosenescence: a decline in immune cell responsiveness that leaves the body less able to clear pathogens and abnormal cells.
A review published in Frontiers in Aging analysed both animal and human studies on exercise and immune ageing. The findings are broadly consistent. Regular physical activity lowers circulating inflammatory markers, reduces the formation of neutrophil extracellular traps (NETs, structures released by immune cells that become damaging in chronic inflammation), and promotes favourable shifts in T cell and NK cell populations.
Effects beyond the immune system
The study also describes effects on blood vessels within tumours. Exercise improves tumour perfusion, reduces hypoxia inside tumours, and restores T and NK cell function in the tumour microenvironment. There is also evidence that exercise shapes the gut microbiome and modulates kynurenine metabolism, a tryptophan breakdown pathway with implications for brain health.
A pill that mimics a workout
Global declines in physical activity make this an urgent question. Researchers are developing so-called exercise mimetics: compounds that replicate exercise’s biological responses without requiring movement. The approach shows promise in animal studies, but human data are largely absent. Optimal exercise dose, and the ideal combination of strength and endurance training for immune ageing, remain open questions. The review calls for mechanistic studies to resolve them and to guide the development of targeted pharmacological strategies.