Habitual exercise can modulate the immune system and thereby delay the start of immunosenescence in the elderly.
Immunosenescence refers to the decline in the normal functioning of the immune system associated with aging. This is a big factor why the elderly has been observed to have poorer response to vaccine systems. This then leads to increased rates of infection and cancer cases in the late adulthood. Recent literature provides evidence that regular exercise contributes to enhanced vaccination responses, associated with a decrease in the number of senescent T-cells, increased rate of T-cell proliferation, and increased phagocytic activity of neutrophils. It has been previously established that regular physical exercise is linked to increased longevity and lower risk of cardiovascular diseases. Individuals who had regular moderate exercise had fewer upper respiratory symptoms. Recent studies have also shown that elderly people who engaged with 6 months of supervised aerobic exercise training had increased T-cell proliferation. Exercise was also found to have effects on the innate immune system as elderly women who have superior aerobic fitness experience had greater NK-cell cytotoxic activity, compared to those who have less aerobic experience. These studies show that habitual exercise can modulate the immune system and thereby delay the start of immunosenescence.