Older adults who move more naturally have lower levels of aging biomarkers and less mobility loss, but structured exercise programs don't lower those biomarkers even though they still prevent mobility loss.

Mechanical and metabolic stress from physical activity activates cellular clearance pathways that reduce the number of senescent cells and suppress their secretory activity

Reduced senescent cell burden leads to decreased secretion of SASP factors including VEGFA, TNFR1, MMP7, IL6, and GDF15 into the bloodstream

Lower circulating levels of SASP factors reduce chronic inflammation, endothelial dysfunction, and activation of muscle catabolic pathways

Attenuated inflammation and reduced muscle breakdown preserve neuromuscular integrity, muscle mass, and physical performance

Oral creatine monohydrate is absorbed from the gastrointestinal tract into the bloodstream

Creatine crosses the blood-brain barrier via the creatine transporter and is taken up by neurons and glial cells

Intracellular creatine is phosphorylated to phosphocreatine by creatine kinase using ATP

During high neuronal energy demand, such as during working memory tasks, phosphocreatine donates its phosphate group to ADP to regenerate ATP

Sustained ATP availability supports neuronal firing and synaptic transmission in brain regions involved in working memory, such as the prefrontal cortex

Improved ATP availability during working memory tasks enhances the stability and speed of neural processing, leading to a small increase in correct responses on backward digit span tasks