Researchers found that men who had a high level of fitness were 79 per cent less likely to develop epilepsy than those with low fitness levels and 36 per cent less likely to develop epilepsy than those with medium fitness levels.
Epilepsy is a brain disease that causes repeated seizures over time.
"There are a host of ways exercise has been shown to benefit the brain and reduce the risk of brain diseases," said study author Elinor Ben-Menachem, with the University of Gothenburg in Sweden and an associate member of the American Academy of Neurology.
In the study, 1.17 million Swedish men were given cycle tests that measured cardiovascular fitness at age 18.
More From This Section
The participants were then assessed for epilepsy for an average of 25 years. During follow-up, 6,796 men were diagnosed with epilepsy.
The proportion of men with high fitness who developed epilepsy in the study was 0.48 per cent, the proportion of men with medium fitness who developed epilepsy was 0.62 per cent and the proportion of men with low fitness who developed epilepsy was 1.09 per cent.
"Exercise may affect epilepsy risk in two ways. It may protect the brain and create stronger brain reserve, or it may simply be that people who are fit early in life tend to also be fit later in life, which in turn affects disease risk," Ben-Menachem said.
The study is published in Neurology, the medical journal of the American Academy of Neurology.