Football players have a higher chance of developing heart rhythm disorders later in life, according to a new body of research being presented at the American College of Cardiology's 67th Annual Scientific Session.

Structural changes in the heart were observed among freshman college players who were part of one study. Researchers at Emory University compared data collected before and after the football season from 136 freshman football players and 44 college freshmen who did not play football. After a single season of play, the size of the aortic root in players had increased, though still in the normal range.

Another study looked at former professional NFL players. The findings indicated that, when compared to the general public, they were five times more likely to have a heart rhythm disorder, such as atrial fibrillation (AFib). Researchers conducted cardiovascular screenings for 460 former NFL players that included an electrocardiogram, echocardiogram, blood tests and a cardiovascular history questionnaire. These results were compared with a sample size of 925 people from the general public with similar demographics to the players in terms of age and race.

This is the first study to find a potential association between AFib and athletes in a strength-based sport.

Dermot Phelan, director of the sports cardiology center at Cleveland Clinic, assured that sports activity does benefit overall health and should not be avoided unless taken to the extremes. "We know that sporting activity increases longevity and has multiple benefits for the cardiovascular system, but our findings seem to suggest that perhaps when you get to the extreme ends that we see in these elite athletes, there may be a negative impact on the heart," said Phelan.

"Players should not assume that leading a healthy lifestyle in terms of regular exercise means that they're immune from developing cardiac problems and, in fact, they may be at higher risk for things like atrial fibrillation," he added.

Previous studies have also shown that there may be an association between professional football and brain disease. This was openly acknowledged by the NFL in 2016. 

"We often think of football players, like all athletes, as the picture of health, but we're gaining this body of knowledge that signals some maladaptive cardiovascular changes and potentially even early cardiac risk in some of these players," said primary study author Jonathan Kim.

Kim is the chief of sports cardiology, assistant professor of medicine at Emory University and lead cardiologist for the Atlanta Falcons. "It suggests we need to pay close attention to the heart health of young football players. Also, future studies will need to focus on understanding the clinical significance of our findings," he added.

The researchers urged football players of all ages to sign up for regular health check-ups to identify possible early signs of cardiovascular disease. 

The study, "Risk of Arrhythmia and Conduction Disease in Former National Football League Players," will be presented on March 12, 2018. Jonathan Kim and Keyur Patel will present the study, "Aortic Root Dilatation Associated with Collegiate American Style Football Participation," on March 10, 2018.