Men and women aged 55 to 80 had improved cognitive performance during an eight-hour daily performance after morning physical activity.
If the same group added 3-minute light intensity walks over the day, it supported short-term memory compared to longer sitting periods, the Baker Heart and Diabetes Institute, and the University of Western Australia research.
More than 65 men and women participated in the Brain Breaks study of participants' attention, decision making, visual learning and working memory along with exercise.
The exercise consisted of walking on a treadmill.
The central protein for the growth of neurons carrying information in the brain was increased for eight hours by exercise, compared to the prolonged session, the study found.
Researcher Michael Wheeler said he should avoid sitting in the long term to maintain optimal cognitive function throughout the day.
"This study shows how relatively simple changes in your daily life can make a significant contribution to your cognitive health," he said.
"It also shows that one day we may be able to do specific types of exercises to improve specific cognitive skills like memory or learning."
The study was published in the British Journal of Sports Medicine.
© AAP 2019