People with Alzheimer's who exercise regularly had less brain damage than those who did not exercise, a preliminary study suggests. The findings may indicate that staying physically fit could slow the brain shrinkage associated with Alzheimer's disease and lead to development of a treatment, researchers hope.

Researchers from the University of Kansas School of Medicine in Kansas City studied 57 people with early Alzheimer's. Their physical fitness was assessed by measuring their peak oxygen demand while on a treadmill, and brain shrinkage was estimated by MRI scans.

Physically fit patients with mild cognitive impairment were found to have less brain shrinkage than those who weren't so well conditioned.

Exercise not only protects the heart health but can also pay off for the brain. Brain function declines as the disease progressively kills nerve cells, causing the organ to lose volume, researchers said.

Previous research has shown that regular exercise boosts thinking and memory in people with normal brain activity by boosting blood flow and elevating growth hormones. The new findings extend this connection to people with Alzheimer's.

The findings are published in the July 15 issue of Neurology.

Alzheimer's disease is a neurodegenerative progressive brain disorder that destroys brain cells, causing problems with memory in old age.