Ongoing registered trials — including functional characterization of CD8+ T cells after supramaximal exercise (NCT06484101), exercise and COVID-19 viral T cell immunity (NCT05019456), and T cell responses to various levels of exercise stress (NCT06638684) — are expected to further clarify how exercise programs influence CD8+ T cell dynamics and immune resilience. The gene discussed is CD8A; the disease is COVID-19.