Get Fit, Improve Memory?
Exercise May Boost Memory Through Brain Blood Flow and New Brain Cells
March 13, 2007 -- Want a sharper memory? Lace up your sneakers. Exercise may
boost memory, and a new study shows how.
The researchers found that exercise boosts blood flow to a brain area
involved in memory -- even in people who aren't in top shape.
Three months of exercise was all it took for people with low levels of
aerobic fitness to increase blood flow to that part of their brain and improve
their scores on memory tests, the study shows.
Additional tests on mice show new brain cells growing in the same
memory-related brain area after two weeks of exercise.
Add it all up, and you've got a good reason to get moving, says researcher
Scott Small, MD, of Columbia University in New York.
"I, like many physicians, already encourage my patients to get active
and this adds yet another reason to the long list of reasons why exercise is
good for overall health," Small says in a Columbia news release.
Studying Exercise and Memory
The new study appears in the early online edition of Proceedings of the
National Academy of Sciences.
First, Small's team put running wheels in the cages of 23 mice. For
comparison, another 23 mice had no access to running wheels.
As expected, the mice with the running wheels in their cages took full
advantage of their exercise gear. They ran on the wheels without any training
Two weeks later, the scientists gave the mice a dye shot to mark new brain
cells in the memory-related brain area. After four more weeks, the scientists
checked the mice's brains.
The exercising mice had more evidence of new brain cells and more blood flow
in the memory-related brain area. The mice with no running wheels in their
cages had no new brain cells and no increased blood flow in that brain
From the Couch to the Treadmill
Next, the researchers focused on people. They recruited 11 healthy
volunteers aged 21-45 (average age: 33) with below-average levels of aerobic
First, participants completed memory tests and an aerobic fitness test. They
also got brain scans using magnetic resonance imaging (MRI).
Next, participants shed their sedentary ways. The researchers assigned them
to work out for an hour, four times weekly for three months, at Columbia
University's fitness center.
The workout routine: Warm up for five minutes at a low intensity on a
stationary bike or treadmill, stretch for five minutes, do 40 minutes of
aerobic training (on a stationary bike, treadmill, stair machine, or elliptical
trainer), and cool down and stretch for 10 minutes.
Work Out, Boost Memory
After three months of exercise, participants repeated the memory tests,
aerobic fitness tests, and MRI brain scan.
Those follow-up tests showed an increase in blood flow to the memory-related
brain area, better scores on the memory tests, and improvements in aerobic
The researchers didn't use a dye test to check for new brain cells in the
exercisers' brains. So the study doesn't prove that exercise boosted human
brain cell production, though exercise apparently had that effect on mice.
The next step is to figure out what exercise regimen is most beneficial for
memory, Small notes. He suggests that doctors may one day be able to prescribe
specific types of exercise to improve memory.
Meanwhile, be sure to check in with your doctor before starting a new
exercise program, especially if you've been physically inactive for a