Stimulate stroke recovery through exercise: by increasing Brain Derived Neurotrophic Factor

Stimulate stroke recovery through exercise:  by increasing Brain Derived Neurotrophic Factor

BDNF , of Brain Derive Neurotrophic Factor, is a neurotrophic factor (or protein) in the brain that is instrumental in the growth of new neurons and new neural synapses.  Moderate exercise has been shown to stimulate increased production of this chemical in the brain, which would in turn create a more optimal environment for neuroplasticity to work it’s magic!

How much exercise is “moderate exercise?” great question!  It’s very difficult to judge how intensely a person is exercising (even for a physical therapist, who does that for a living!)…but one fairly easy way is to monitor your heart rate and keep it within a certain training range.  A commonly used range for moderate intensity exercise is about 70-80% of your maximum heart rate.  So first you calculate your maximum heart rate by subtracting your age from the number 220.  (for example, if you are 50 years old, your maximum heart rate would be 170)  Then you calculated 70-80% of this maximum heart rate (if you are still 50, then your 70-80% of max heart rate range would be 119 to 136).  Keep in mind that after a stroke, EVERYTHING takes more energy!  So any from of activity or exercise could elevate your heart rate more than it would elevate the heart rate of somebody who hasn’t had a stroke.

Perhaps I should back up for a minute and explain how to calculate your heart rate.  Get a heart rate monitor.  There.  done.   OR you could do it the old-school way by finding your pulse on the side of your neck (under your jaw, about halfway between your ear and your chin), or on your wrist (on the palm side, closer to your thumb than your pinkie).  Use a light pressure with your first two fingers to feel the pulse, and simply count the beats for a minute (or count them for 15 seconds and multiply by four).

Ok, so  we’ve figured out how intensely to exercise…….now how long should we do it?

The first study listed below used 30 minutes exercise sessions to research the increase in BDNF during exercise.  This is also a commonly prescribed time for aerobic activity.  Most sources will also tell you that the 30 minutes can be split into 15 minute increments, without significantly decreasing your benefit from performing the exercise.

Here’s what we’ve got so far:  30 minutes of exercise at 70-80% of your max heart rate

• Let’s be honest here, 30 minutes can be a long time for somebody who has survived a stroke.  I’ve never had a stroke, and 30 minutes can seem like a long time for me, too!  Don’t expect to hit this 30 minute goal on your first try.  Start small (maybe no more than 3-5 minutes), and gradually work your way up to it.

Now we’ve just got to figure out the mode of exercise. In other words, what are you going to do for this 30 minutes to keep your heart rate in that range?  Here are a few suggestions:  stationary bicycle, upper body ergometer, walking, some type of Wii game, elliptical machine, water exercises or a water aerobics class.  Just make sure your are safe to participate in any of these activities before trying them.

Here are a few links to more info on BDNF and exercise:

http://www.ncbi.nlm.nih.gov/pubmed/17414812 – The effect of acute exercise on serum brain-derived neurotrophic factor levels and cognitive function.

http://circ.ahajournals.org/cgi/reprint/109/16/2031 – American Heart Association circulation on physical activity and exercise recommendations for stroke survivors

http://hdlighthouse.org/treatment-care/care/hdltriad/exercise/updates/0001exercise2.php -”Exercise & BDNF”