Exercise helps young men lower their risk of developing epilepsy later in life, according to a new study.

Epilepsy is a brain disorder in which the affected person has several seizures over time. An estimated 2 million people living in the U.S have epilepsy with another 140,000 developing the condition each year. Epilepsy costs about $15 billion to the U.S. economy, CDC says.

"There are a host of ways exercise has been shown to benefit the brain and reduce the risk of brain diseases," said Elinor Ben-Menachem, PhD, with the University of Gothenburg in Sweden, one of the study authors. "This is the first study in humans to show that exercise may also reduce the risk of epilepsy, which can be disabling and life-threatening."

The study was based on over 1 million Swedish men who had undergone medical examination when they enlisted for mandatory military service at age 18. The men were then re-examined when they were 25 years old. The follow-up tests showed that nearly 6,800 men had developed epilepsy.

Researchers found that men with the highest levels of fitness were 79 percent less likely to have developed the condition when compared with men who had lower fitness levels at the start of the study.

Other studies conducted on exercise have shown that it reduces brain damage and improves life satisfaction.

 "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 in a news release.

The study was published in the journal Neurology.