Physical Activity and Immunity in the Elderly for the Post-COVID-19 Pandemic Era: A Literature Review

OBJECTIVES This study aims to summarize previous studies on the relationship between regular physical activity and the immune system in the elderly, and discuss optimal exercise modes to maintain immunity in preparation for novel infectious diseases that may continue to appear.METHODS This study referred to the academic papers based on the electronic database, and they were searched using the following keywords: physical activity, immunity, elderly, and COVID-19.RESULTS The elderly are more vulnerable to infectious disease such as the novel coronavirus disease 2019 (COVID-19) than other age groups because of lower physiological function and immune surveillance, consequently leading to higher severity of and mortality. Many studies on physical activity and immunity have confirmed that regular physical activity enhances immunity in the elderly population. Physical activity can delay immunosenescence and increase immune resilience by maintaining the function of the innate and acquired immune systems. Because the elderly have low physical fitness, physiological function, and immunity, exercise prescription for the elderly must be approached very carefully and in detail, considering various exercise modes such as exercise intensity and amount. As confirmed in previous studies, homebased light physical activity is a convenient, safe, and effective strategy for the health of the elderly.CONCLUSIONS In this study, balance training using body-weight is a good method of home-based physical activity for the elderly, because it not only improves immunity by increasing physical fitness but also prevents frequent falls by increasing the balance ability of the lower extremities. Future studies should be conducted on various exercise modes and optimal exercise training to improve immunity in the elderly.