5. Denver, Colorado
In Denver, it isn't at all strange for guys to roll into the office sporting spandex bike shorts and shaved legs. Outdoor fitness is ingrained in Denver's culture, and it's a big reason why the area's many transplants moved to this always-sunny natural playground in the first place. When in the city, residents make use of the many golf courses, swimming pools, and biking and running trails, and when they break away from urban life – which is often – there are endless hiking and mountain biking trails, rock climbing routes, and ski hills to explore nearby. Also, with its steep hills and canyons just outside the city, the area offers some of the best road cycling and running trails anywhere, which is why pro athletes from around the world go there to train. Not surprisingly, Denverites eat healthy to fuel their active bodies, which helps keep heart disease rates low.