Exercise. We spit it out like it's a 4 letter word. Most of us loathe it. Yes, there are the dedicated few who actually make use of their gym membership for which they have funds withdrawn painlessly every month. But for the vast majority of the population, our physical activity consists of walking to the feeding trough to stuff our faces and pointing the remote control to change the TV channel. Thank goodness for Wii, and now PlayStation Move & XBox 360 Kinect to get some of us off our bottoms. I'm ranting about this since a recent study demonstrated that walking more was associated with greater brain volume and lower risk of cognitive loss.
The authors followed 299 adults (average 78 years old) who were free of cognitive impairment at baseline. Brain MRI was performed at baseline & year 9 followed by reassessment of cognitive function at year 13. All the while, they evaluated the amount of walking performed on a regular basis. The range of walking varied from none to 300 blocks per week with an average distance of 56 blocks (or 8 blocks per day 7 days per week). However, the authors concluded that one needed to walk 72 blocks weekly or 10 blocks daily without fail in order to preserve and actually increase brain volume. This greater amount of gray matter was then associated w/significantly lower risk of cognitive impairment just 4 years later.
Take home point? Physical activity is protective of brain function as we age which is imperative as our Baby Boomers reach retirement and the age at which risk of dementing illnesses increases dramatically. But I can hear it now. How long is a block? Here in Las Vegas, the major street intersections are a mile apart (granted there are more frequent intersections in between). But the authors did declare the 72 blocks equivalent to 6-9 miles.
Now if this study isn't convincing enough to get you off your sofa, a study published in July came to a similar conclusion in women. Likewise studies from August 2009, September 2008, July 2008, May 2008, and October 2006 all point towards the same conclusion that an increase in physical activity is associated with an increase in cognitive function & lower risk of dementia. So that you won't later forget that you should have.