Brain Health 3: The Wonders of Exercise

February 01, 2011

Brain Health 3: The Wonders of Exercise 

 Date:  Feb 2 2011 Andel et al  J Gerontol A Biol Sci Med Sci (2008) 63 (1): 62-66. Competency: Brain Health 

This is the hard one.  Your brain needs you to exercise.  And you really don’t want to.  You want to sit on the couch and watch CSI.  To become motivated to exercise you have to have some really primal forces pushing you.  How about not eating if you don’t walk?  Or, no sex for you if you don’t run a bit….  In our evolutionary past that was basically it.  We had to run to chase down lunch (gazelles and kudu) or to get away from our predators (lions).  Or, we had to be on the move to find the next seasonal food source that might be a couple of miles away.  

If you examine the most primitive hunter-gatherers on the planet (Hadza in Tanzania) you find folks who hunt around the clock whenever an opportunity arises, walking miles to kill one baboon to share among twenty individuals.  A lot of walking for a little bit of food.  We evolved walking, running, and stressing our muscles a lot. 

 Life is easier now.   You may have to climb five stairs in your tri-level house on your way to breakfast.  And maybe you have to walk down to the mailbox to leave an envelope for the postman.  And that’s about it.  There is all that standing around the water cooler, of course.  But come on, you aren’t getting sweaty.  Put a pedometer on and you only walk about 1500 to 2000 steps a day.  And your brain is gradually turning to mush. 

 The details of why exercise is so good for you are not completely known.  It’s likely something to do with osteocalcin, a marvelous little protein washed out of bones with exercise that makes you much more sensitive to insulin.  And with lower insulin you have less inflammation.  Something there is in your brain nurse cells called glial cells that wrap themselves around your regular brain cells and protect them that doesn’t like insulin, but still need lots of glucose as energy.  If you want a healthy brain you want glial cells that never get activated.  You want them to be calm and relaxed and mellow.  And to get to mellow, your glial cells need to have you exercise. 

 The research is just stunning.  Here is just one example.  Andel in the Journal of Gerontology published a lovely twin study, following some 3100 pairs of twins in Sweden for thirty years.  He was able to find 90 pairs who developed Alzheimer’s in one and not the other.  The effect of exercise was pretty big.  Light exercise like gardening and walking reduced the risk of dementia by as much as 40%.  Sweaty exercise with  sports reduced the risk as much as 65%.  And that was 31 years later.  But this column has reviewed this idea many times.  We’ve reviewed that even light exercise measurably affects your memory within just 6 months, and the effect lasts 18 months afterward. 

 WWW.  Want a healthy brain?  It’s pretty simple.  You just have to move more than you are moving now.  10 K a day is a very interesting number.  You add that much walking to your 2K day, and you get to keep your brain.  It will take you about an hour. Find a friend.  Make it a habit.  Join the Milwaukee Hiking Club.   I’m there and would love to introduce you.  5 hikes a week, rain or shine.  No cost.  Nice people.  We walk about 5 miles at a time.  And laugh.

Column written by Dr John E Whitcomb, MD, Brookfield Longevity, Brookfield, WI.