Maltais M, et al. - Given that molecular and physiological processes that result in changes in the organism characterize the biological process of aging, but there is no consensus regarding the measurement of biological aging, and physical activity (PA) could represent a potential marker of an aging phenotype, therefore, addressing this topic, researchers performed this study wherein they evaluated measurements of body composition, muscle quality, blood biochemistry, and neurodegeneration during three years and measured levels of PA by means of a self-reported questionnaire. The evolution of brain and hippocampal volume in a significant correlation with maintained low levels of PA vs inactivity was demonstrated by three-year progression of PA levels. Findings revealed the association of PA levels with some elements of biological aging.