Unsurprisingly, elite athletes are at lower risk of developing cardiovascular problems than the rest of us. One group, though, is an exception to the rule. American football linemen have a higher risk of heart problems than the general population, and a recent study published in JAMA Cardiology suggests the players’ rapid weight gain – an average lineman weighs 136kg – is to blame. "What we're seeing is a young, otherwise healthy group of people that gain weight and develop thick hearts and stiff arteries," said the study’s lead author Aaron L. Baggish, MD. "If you took a 20-year-old who didn't play a sport and asked them to gain 40 pounds, no one would ever question whether that was unhealthy."