Exercising mice: Better memories, more brain cells
Mice given access to exercise wheels after they reach old age do better at remembering their way through mazes and develop more new brain cells than older mice who stay sedentary, researchers from the Salk Institute report in the Sept. 21 Journal of Neuroscience. Running also boosts new brain cell development in young mice.
Mice with exercise wheels are impressive runners: older mice log an average of 2.4 miles each day, while younger mice average 3 miles.
"This study suggests it may never be too late to start exercising to maintain your brain," says William H. Thies, Ph.D., Alzheimer's Association vice president, medical and scientific affairs. "Of course, the usual cautions about translating rodent results to humans apply here. It's also important to recognize that caged mice have a very strong drive to run on exercise wheels, as shown by the long distances they log. In this study, older mice clocked an average of 2.4 miles each day, while younger mice averaged 3 miles. People typically have trouble mobilizing themselves to comply with exercise recommendations."Even with motivation, many older adults live in situations where safety issues or logistics are significant barriers to getting out and keeping active," Thies notes. "So our discussion as a society needs to extend beyond individual motivation to policy and planning issues."
These Salk Institute researchers also found that new brain cells formed in older mice do not appear to differ from those in younger mice in terms of overall size and shape or the length and number of connections with other cells. The researchers speculate that older mice who started running at a younger age and continued to run might have performed even better on memory tests.
For more information, please see:
- Alzheimer's Association Maintain Your Brain® campaign
- Home page of study principal investigator Fred Gage
- Related article: Exercise could build brain cells in elderly - USA Today