Study Finds Midlife Aerobic Exercise Linked to Younger Brain Age

A study of 130 inactive adults aged 26 to 58 found that those who completed a supervised aerobic exercise program for one year showed brains that appeared functionally younger on MRI scans. Researchers randomly assigned half the volunteers to twice-weekly supervised workouts on treadmills or bicycles plus additional home sessions totaling at least 150 minutes per week.

The remaining participants maintained their usual routines. After 12 months, brain scans showed the exercise group had reduced their average brain age by roughly seven months compared with baseline measurements. The control group’s brains appeared slightly older than at the start of the study.

Earlier studies had shown that aerobic activity increases production of new brain cells and blood vessels in animals and enlarges the hippocampus in older adults. Most of that work examined people over age 60. The current trial focused on midlife to test whether exercise could alter brain aging before typical cognitive decline begins.

Brain age was calculated by comparing each participant’s MRI results with a large database of scans from people of known ages using machine-learning algorithms. Lower brain age relative to chronological age has been associated in other research with reduced dementia risk.

The study found no direct link between changes in fitness measures such as blood pressure or body weight and the observed shift in brain age, suggesting other biological pathways may be involved. Researchers stated they plan future work examining specific brain regions, cognitive test scores, and different exercise intensities.