A new study has found that prolonged periods of sitting are significantly associated with cognitive decline and brain shrinkage linked to Alzheimer’s disease – even in individuals who exercise regularly.
Published in Alzheimer’s & Dementia: The Journal of the Alzheimer’s Association, the research sheds light on how everyday habits, like how much time we spend sitting, may play a powerful role in brain health as we age.
A closer look at study
By the numbers:
Researchers from Vanderbilt University Medical Center and the University of Pittsburgh analyzed more than 400 adults aged 50 and older.
Participants were asked to wear activity-tracking devices for ten consecutive days, providing detailed data on how much time they spent sitting or lying down. The researchers then analyzed this sedentary behavior against cognitive tests and brain imaging over a seven-year period.
The study found that individuals carrying the APOE-e4 allele – a known genetic marker for Alzheimer’s disease – were particularly susceptible to the negative effects of sedentary behavior.
Individuals who were more sedentary experienced greater cognitive decline and notable shrinkage in brain regions critical for memory and Alzheimer’s development.
FILE: Office space. (Credit: Tom Lee/Construction Photography/Avalon/Getty Images)
In fact, the researchers said its sample of participants were quite active while wearing the devices, with 87% of participants meeting the CDC recommendation of at least 150 min of MVPA per week.
What they’re saying:
The team said this provides “strong evidence that even among a physically active cohort, such increased activity is not protective from the impact of greater sedentary behavior and brain health, especially among APOE-e4 carriers.”
This means the effects were observed regardless of participants’ exercise routines.
Lifestyle modifications may be beneficial for those with elevated risk
Dig deeper:
According to the researchers, these findings are particularly important in the context of aging, as mobility limitations and greater sedentary time increases in older adults.
The researchers suggest that lifestyle modifications may be especially vital for those with an elevated genetic risk.
“Reducing your risk for Alzheimer’s disease is not just about working out once a day,” lead researcher Marissa Gogniat told Consumer Reports. “Minimizing the time spent sitting, even if you do exercise daily, reduces the likelihood of developing Alzheimer’s disease.”
The study said that healthcare professionals might consider assessing not only a patient’s exercise regimen but also the amount of time they are sedentary throughout the day, recommending a reduction in such sedentary behavior in addition to increasing daily physical activity.
They said future work may consider exploring the underlying biological mechanisms that contribute to these associations, which could inform treatment and prevention efforts.
Sedentary behavior linked to diseases
The backstory:
Previous studies have said that “sitting is the new smoking,” suggesting that a sedentary lifestyle was bad for your health.
A JAMA Network study published last year followed nearly 500,000 people for 12 years and found those who sat at work had a 16% higher risk of mortality from all causes and a 34% higher risk of heart disease compared to those who predominantly didn’t sit at work.
RELATED: Here’s how much exercise you need to offset the effects of sitting too much
But, another study, published in 2023 in the British Journal of Sports Medicine found that just 22 minutes of brisk walking or a similar activity could offset the risk of prolonged sitting.
Nearly seven million people in the U.S. are currently living with Alzheimer’s, and the number is expected to reach 13 million by 2050, according to the Alzheimer’s Association.
The Source: Information from this story was provided by a study titled: Increased sedentary behavior is associated with neurodegeneration and worse cognition in older adults over a 7-year period despite high levels of physical activity, which was published on May 13, 2025. Previous FOX Local reporting also contributed. This story was reported from Los Angeles.
