How to Grow Your Brain with Exercise

The Theory

The brain is plastic; it isn’t fixed rigid from the day you were born to the day you will die. Brain cells can grow or die, they can strengthen or weaken throughout your life. You’ve probably heard the saying ‘when neurons fire together, they wire together.’ This is a fancy way of saying that, if you do something over and over again, you’ll get better and better at it and, eventually, you’ll be able to do that something without even thinking about it. Remember when you learnt to ride your bike? It was a nightmare at first, then you had stabilisers, then you were as free as a bird, flying down the road. That was the result of your brain’s neurons firing together over and over again and eventually wiring together so tightly that you didn’t have to think about pedalling or steering or braking any more.

Only mobile creatures need brains. Brains are very expensive things to run, they cost us a lot in terms of energy. If we didn’t really need a brain, we wouldn’t have one. There’s a particular mollusc that is born with a brain so that it can move across the rocks away from its birthplace. When it has found a new home, it doesn’t need the brain anymore so it eats it. Yum. You could say that thinking is the internalisation of movement, therefore it is only to be expected that exercise should have a profound effect on the brain.

And indeed it does. Exercise elevates the following chemicals in your brain:

  • Serotonin, which controls your mood.
  • Dopamine, which is your brain’s ‘reward centre’, linked with movement and learning.
  • Norepinephrine, which controls your attention and motivation.
  • BDNF, dubbed ‘MiracleGro for the brain’. This creates new branches of synapses. In other words: it grows brain cells.

And the more exercise you do, the more it spikes growth.

The Workout

The brain can’t learn while exercising, but blood goes to the prefrontal cortex immediately after exercise, making it ripe for learning something new.

  • Both aerobic (e.g. running, cycling) and complex activities (e.g. playing the piano, martial arts) are important.
  • Aerobic exercise elevates executive function neurotransmitters. This will create new blood vessels and new cells.
  • Complex activities increase BDNF, which strengthens and expands synapse networks. 
  • Tennis is a good example of an activity that combines both aerobic and complex activity. Other examples are yoga, pilates and dancing. Dancing to an irregular rhythm, like the tango, is particularly good for improving your brain’s plasticity.
  • Try to hit a least 35 minutes at 60-70% intensity (for women) or at your maximum heart rate (for men).


Information from this article is taken from Spark! The Revolutionary New Science of Exercise and the Brain by John J. Ratey and Eric Hagerman.

What do you think?