Heidi Musser wasn't allowed to participate in physical education classes in high school because she was blind. Musser has heard that same "you're blind, so you can't play" message most of her life.

Musser, though, was determined to prove otherwise. And prove it she has. Musser has competed in more than 20 triathlons, competitions which combine swimming, biking and running. She's also finished one Ironman Triathlon, which consists of a 2.5-mile swim, 112-mile bike and a 26.2-mile run, which is a full marathon.

Few sighted people have competed in a triathlon, much less an Ironman, and Musser's example shows what can be accomplished through determination and perseverance. It's also just one of many stories of people with disabilities being able to accomplish great things in sports by putting their mind to it.

Musser may have had more to overcome than most of us to get there, but that's what makes her story, and her lesson to all of us, so compelling.