How Does Exercise Change our Brains?


Many incredible things happen in our body when we exercise; our heart, muscles, bones and lungs all get stronger among other positive changes. Some of the most fascinating changes however occur in our brains!  Here are some of the wonderful adaptations that occur in our brains when we exercise: 


Memories are made 

Exercising has the capacity to improve our memory and the strength of these memories. Exercise increases brain-derived neurotrophic factor (BDNF) which is a protein in the brain that promotes learning and memory, making it easier to take in information and formulate long term memories. What better motivator to get moving than to preserve our precious memories! 

Stress levels decrease 

Exercise has been found to decrease the number of stress receptors in the hippocampus (the part of the brain responsible for emotional memory recall and regulation). Fewer stress receptors means that we have a decreased response to the stress hormones in the brain.  

There is also a phenomenon labelled the ‘runners high’. Exercising causes a massive release of endorphins which are chemicals produced by the nervous system to cope with pain or stress, they’re typically referred to as our ‘feel good’ hormones. This mechanism (which can be brought about by just 10-30 minute bouts of exercise) is thought to be the mechanism that can indirectly decrease stress and reduce feelings of anxiety and depression. 

The brain gets fed nutrients 

Exercise increases blood flow to the brain which simultaneously delivers vital oxygen and nutrients. The brain has a very high metabolic demand which means that good cardiovascular circulation is vital, exercise is a great way to increase circulation and allow the brain to do its job more efficiently (i.e. better brain power!) 

Increase your levels of Joy 

Exercising provides the brain with small doses that stimulate the brains reward centres. Regular exercise and hence small doses of pleasure and motivation can rewire the brain to increase circulating levels of dopamine as well as increase the number of dopamine receptors. This means that you will increase your sensitivity to dopamine therefore increasing your capacity to feel joy. Did you know that adults lose up to 13% of the dopamine receptors in the reward system every decade? This leads to less enjoyment as we age, but exercise is a great way to prevent this decrease as well as manage stress levels as previously stated.

New brain cells are born and cognition improves 

Exercise has been found to promote neurogenesis (the process of forming new neurons or nerve cells in the brain). Studies have shown that running can create new brain cells in the hippocampus, as well as improve the health and efficiency of synapses in this region (the parts of the nerve cells that communicate with other nerve cells to pass messages on). 

Increased protection to neurogenerative diseases 

Think of the brain as a muscle, the more you work it the stronger it gets! Via increased strength of the hippocampus and prefrontal cortex (both of these areas are commonly affected by neurodegenerative diseases like Dementia or Alzheimer’s), we can decrease our likelihood of acquiring such conditions. Unfortunately these neurodegenerative diseases have no cure, so let’s do what we can to help reduce or delay the onset – exercise regularly! 


Exercise really does have the capacity to enhance our daily lives not only by improved physical health but also due to all of the above changes that are occurring in our brains. The key is to be consistent with our exercise to maximise these positive brain changes. Let’s aim for a total of 2.5-5hrs of moderate physical activity per week, ensuring that on at least 2 days per week we are completing muscle strengthening exercises.


Keely MacLean 

Clinical Exercise Physiology (Student)