It 's well known that exercise can make your muscles bigger . Now , a study has found it may make your brain larger , too . Physical activity can increase grey matter in the brain , increasing the size of areas that contribute to balance and coordination , according to Health Day news . The changes in the brain may have health implications in the long-term , such as reducing the risk of falling , said the study 's author , Dr Urho Kujala , of the University of Jyvaskyla . Scroll down for video . Exercise can increase the size of areas of the brain that contribute to balance and coordination , a study found . It could also reduce the risk of being immobile in older age , he added . Dr Kujala said physical activity has already been linked to a number of health benefits , such as lower levels of body fat , reduced heart disease risk factors , better memory and thinking , and a lower risk of type 2 diabetes . But he and his team wanted to understand how exercise affects the brain . They recruited 10 pairs of identical twins , who were all men aged 32 to 36 years . Focusing on twins , who have the same DNA , would allow researchers to see how their environment affects their bodies . In each pair of twins , one brother had exercised more over the past three years than the other , though they reported they carried out similar levels of exercise earlier in their lives . Dr Kujala said : 'On average , the more active members of twin pairs were jogging three hours more per week compared to their inactive co-twins . ' The twins had MRI scans of their brains so researchers could see whether physical activity had any impact on the size of their brains , and specific regions . Exercise did n't seem to affect the size of the brain as a whole , Dr Kujala said . But there was a connection between more activity and more brain volume in areas related to movement , he added . Previous research found exercise is linked to lower levels of body fat , a reduced risk of heart disease , better memory and thinking , and a lower risk of type 2 diabetes . The twins who exercised more did a better job of controlling their blood sugar , which reduces the risk of diabetes , a finding which is already well-known . The study was published in the journal Medicine & Science in Sports & Exercise . It comes after US researchers found regular exercise can also make you smarter . University of South Carolina experts found regular treadmill sessions create more mitochondria - structures in the cells that produce the body 's energy - in the brain . This energy boost helped the brain to work faster and more efficiently , effectively keeping it younger , researchers said . In the short term this could reduce mental fatigue and sharpen your thinking in between gym sessions . And building up a large reservoir of mitochondria in the brain could also create a 'buffer ' against age-related brain diseases such as Alzheimer 's .
Study : The New York Times