Walking on a treadmill significantly improves the health and mobility of the stroke victims, a new research from Johns Hopkins University School of Medicine concluded.

The study's results showed  that patients' brains may retain the capacity to rewire through a treadmill exercise program months or years after conventional physical therapy has ended.

"This is great news for stroke survivors because results clearly demonstrate that long-term stroke damage is not immutable and that with exercise it's never too late for the brain and body to recover," says Daniel Hanley, M.D., professor of neurology at the Johns Hopkins University School of Medicine.

The researchers have recruited 71 patients who had a stroke at least six months earlier, with an average time lapse of nearly four years. At the study's onset, half of the subjects could walk without assistance, while the rest used a cane, a walker or a wheelchair.

All of the subjects, separated into two random groups regardless of disability, were tested for mobility and aerobic capacity (also known as VO2 peak), a measure of cardiac fitness. Thirty-two patients drawn equally from both groups underwent functional magnetic resonance imaging (fMRI) to assess brain activity linked to moving their legs in a walking motion.

One group then participated in an exercise program that principally involved walking on a treadmill three times a week for up to 40 minutes, assisted by a supporting sling and tether if needed. With the second group of patients, therapists assisted the patients in performing stretching exercises for the same period of time.

Walking speed for the treadmill group increased 51 percent compared to about 11 percent faster for those in the stretching group. Ground walking speed among the treadmill exercisers increased 19 percent, compared to about 8 percent for the stretchers. The treadmill exercisers also were significantly more fit at study completion, with VO2 peak increasing by about 18 percent. VO2 peak decreased slightly in the stretching group.

"This suggests that the brain is responsible for the improvement we saw in patients' walking ability. It seems to be recruiting other regions to take on the job of areas damaged by stroke," says Andreas Luft, M.D., a visiting researcher who worked at the study.