Increased sedentary behavior is associated with neurodegeneration and worse cognition in older adults over a 7‐year period despite high levels of physical activity

In older adults, spending more time sitting is linked to poorer episodic memory when physical activity is not considered, but this link disappears when physical activity is taken into account.

Older adults who spend more time sitting experience a faster decline in their ability to name objects and process information quickly over seven years, even when accounting for how much physical activity they do.

Older adults aged 60–80 who spend more time sitting each day, even if they meet physical activity guidelines, show a faster yearly decrease in hippocampal volume and lower performance in processing speed and naming ability over seven years.

In older adults, more time spent sitting is linked to less cortical thinning in brain regions affected by Alzheimer’s disease, but this link becomes weaker when physical activity is taken into account.

In older adults with the APOE-ε4 gene variant, more time spent sitting is linked to smaller total gray matter and smaller frontal and parietal brain regions at the time of measurement, regardless of how much physical activity they do.

Prolonged sitting reduces the brain's ability to flush out metabolic waste, which leads to buildup of waste products and results in brain fog and long-term cognitive decline.