Cognitive decline is a natural process that accompanies aging. In some cases, such as in sarcopenia-burdened or diseased older adults, the disease course may be more rapid. Declining cognitive function is associated with changes in the central nervous system per se or peripheral triggers that impair cognition. This review discusses issues related to central, central-peripheral, and peripheral factors that enhance cognitive deterioration, such as cortical thickness, cerebral white matter structure and function, blood-brain barrier (BBB) disruption, insulin resistance, inflammation, and vascular dysfunction. BBB permeability appears to be a critical point for factors associated with aging that may accelerate cognitive decline. Thus, we provide an in-depth analysis of the central-peripheral crosstalk. Additionally, we discuss high-intensity interval training (HIIT) as a promising strategy to counteract changes that accompany the aging process. Resistance (RHIIT) and aerobic (AHIIT) may be beneficial for cognitive health among the elderly, but their lack of empirical confirmation is a huge gap in the research.