Evidence has shown that regular physical activity can improve cognitive function and brain plasticity. However, research has been unclear in proving how much exercise is needed and how long these benefits can last for. A recent study conducted at the University of Adelaide in Australia suggests that one 30-minute session of vigorous exercise can lead to changes in the brain that make it more “plastic,” including improvements in memory and motor skill coordination.  

"Although this was a small sample group, it helps us to better understand the overall picture of how exercise influences the brain,” lead researcher Associate Professor Michael Ridding said in a statement. “We know that plasticity is also important for recovery from brain damage, so this opens up potential therapeutic avenues for patients. Further research will be required to see what the possible long-term benefits could be for patients as well as healthy people."

Ridding and his colleagues recruited a small group of adults in their late 20s and early 30s who were asked to ride exercise bikes for a period of 30 minutes. The team of neuroscientists monitored changes in the brain directly after the exercise session and again 15 minutes later. Results show that even one 30-minute session of physical activity can improve the brain’s plasticity, or its ability to change physically, functionally, and chemically. Positive changes in the brain were sustained 15 minutes after exercising.

"We saw positive changes in the brain straight away, and these improvements were sustained 15 minutes after the exercise had ended," Ridding added. "Plasticity in the brain is important for learning, memory and motor skill coordination. The more 'plastic' the brain becomes, the more it's able to reorganise itself, modifying the number and strength of connections between nerve cells and different brain areas. This exercise-related change in the brain may, in part, explain why physical activity has a positive effect on memory and higher-level functions."

A similar study conducted at the University of Illinois at Urbana-Champaign found that regular exercise can benefit the brain’s supply of white matter, also known as “the subway of the brain” due to its ability to connect different regions of grey matter in the cerebrum to each other. Researchers assessed the link between physical fitness and the brain in 24 9- and 10-year-olds. Children who were more physically fit had thicker and denser white matter, meaning they had a greater capacity for memory, attention span, and cognitive efficiency.

Source: Ridding M, et al. Just 30 minutes of exercise has benefits for the brain. University of Adelaide. 2014.