June 25, 2025
Middle-aged men and women who opted to cycle or walk had a lower risk of developing dementia years later than their peers who rode in a car or took a bus, according to a new report. Researchers who surveyed older adults found that those who chose an active mode of transportation, such as walking or cycling, had a lower risk of developing Alzheimer’s disease or other forms of dementia over the next 13 years than their peers who drove or took public transport.
For the study, researchers at Huazhong University of Science and Technology in China and the University of Sydney in Australia looked at 479,723 men and women who were part of the U.K. Biobank, a large and ongoing study of the lifestyle habits and health of people in Britain. Their average age was 56, and none had dementia at the study’s start.
The researchers did not look at work commutes, but rather how participants traveled during their free time or to run errands. They assessed travel modes by asking participants: “In the last four weeks, which forms of transport have you used most often to get about (not including any journeys to and from work)?”
They grouped them in four general travel categories: those who were non-active, choosing a car or public transport; walking; mixed-walking, a combination of non-active and walking; and cycling or mixed-cycling, a combination of cycling and other modes of transport. Almost half the participants were in the non-active group, compared to almost 7 percent in the walking only group, 37 percent in the mixed-walking group, and 7 percent in the cycling group.
Over the next 13 years, 8,845 of those in the study group developed Alzheimer’s disease or another form of dementia. Those who biked or included cycling at least some of the time had a 22 percent lower risk for Alzheimer’s disease, the most common form of dementia; a 17 percent lower risk for late-onset dementia, occurring at age 65 or older; and a 40 percent lower risk of early-onset dementia, before age 65.
Cycling appeared to be particularly beneficial for the brain. Examination of brain scans showed that those who cycled at least part of the time not only had a lower dementia risk, they also tended to have a greater volume of the hippocampus and other brain regions critical for memory. Smaller hippocampal volume is associated with a greater likelihood of developing Alzheimer’s disease.
Aerobic activities like cycling or walking are known to have brain-protective benefits. Cycling, more so than gentle walking, may help to boost blood flow to the brain, stimulate the creation of new neurons, and reduce levels of body-wide inflammation, which may play a role in Alzheimer’s onset. Cycling also requires heightened levels of navigation and spatial engagement, which may help to keep the brain sharp.
Those who carried the APOE-E4 gene variant, which increases the risk of developing Alzheimer’s disease, did not show as pronounced benefits from cycling as their peers who didn’t carry the gene variant. Still, APOE-E4 carriers did show some benefits from cycling. Taken together, the results suggest that active travel remains an effective strategy for enhancing brain health, the authors note.
Interestingly, in this study, walking alone was not associated with a lower risk of Alzheimer’s disease, though other studies suggest that an active walking program can be good for the brain. Those who combined walking with driving, however, did show brain benefits. The authors suggest that driving, which requires navigating traffic and other cognitive challenges while facilitating social connection, may have some brain benefits over more passive activities like taking a bus. “Driving may support cognitive health by promoting an active life space and by engaging the brain,” the authors note.
This study, published in the journal JAMA Network Open, showed only an association between active modes of transport and better brain health and cannot prove cause and effect. But numerous studies show that physical activity is good for the heart, and what’s good for the heart is good for the brain.
“Our findings suggest that promoting active travel strategies, particularly cycling, may be associated with lower dementia risk among middle-aged and older adults,” the authors conclude.
So next time you are heading out to enjoy the neighborhood, consider hopping on a bike. Just don’t forget the helmet.
By ALZinfo.org, The Alzheimer’s Information Site. Reviewed by Eric Schmidt, Ph.D., Fisher Center for Alzheimer’s Research Foundation at The Rockefeller University.
Source: Cunpeng Hou, Yaqi Zhang, Fieyang Zhao, et al: “Active Travel Mode and Incident Dementia and Brain Structure.” JAMA Network Open, June 9, 2025
