We often describe others as having a "big heart," but depending on who they are they might have an over-sized heart in a very literal sense. Particularly if they've ever competed in the Tour de France, as research shows that Tour de France athletes have hearts that are 20-40% larger than average. Scientists have noted that almost any athlete that trains extensively will adapt by growing a larger heart, but the strenuous bicycling competition involving 3 weeks of bicycling up and down mountains obviously takes it to the extreme!
