Exercise is important and research never fails to remind us of this fact.

A new study has shown the importance of regular exercise for postmenopausal women in avoiding arrhythmia.

The study researchers found that postmenopausal women who were physically active had up to a 10 percent lower risk of developing atrial fibrillation.

Atrial fibrillation is an irregular and possibly rapid heart rate that leads to poor blood flow throughout the body.

The study, published in the Journal of the American Heart Association, found that this decreased risk also extended to women even if they were obese. It looked at more than 80,000 participants.

The researchers asked women how often they walked outside or engaged in physical activity hard enough to sweat.

The study also found that the more physical activity women did, the more of a reduced risk they had - up to 10 percent.  

"We pretty clearly show that in this older population, the more they exercised, the less likely they were to develop atrial fibrillation - and the obese women were the ones who benefited most from this exercise," said Dr. Marco Perez, study author.

This study is somewhat contrary to other studies that have suggested that strenuous activity may actually lead to atrial fibrillation. These studies were done in elite athletes, but it caused doctors and researchers to wonder if the findings could generalize to normal people as well.

"This study shows that moving, keeping a body in motion, is a good thing even if you have risk factors for the disease," said Dr. Gordon Tomaselli, spokesman for the American Heart Association. "You can't use atrial fibrillation as an excuse for not being physically active, if you're an average guy or gal."

He also said the increased benefit for obese women is important because physical exercise already cuts their risk of developing the disease, but if it also leads to them losing weight, it could benefit them more in that respect.

According to the study, approximately 1.1 million women in the US have atrial fibrillation, and this number is expected to increase 2.5-fold in the next 50 years.

Because the study was an observational study, however, no cause-and-effect relationships can be drawn.