I did
Run for the Cure on Sunday (I think in the USA, they call it
Race for the Cure. My goal was to run the full 5 km (that's 3 miles for my American sisters....

) without stopping and I did!
www.cbcf.org
It was a VERY emotional experience, and I wavered between the elation of the "runner's high" with that of intense sadness. I don't know if the Runs do this in the USA, but in addition to your running number, you also can wear a "I'm Running For _____" bib.
I filled out the name of a woman in Junior League who was just diagnosed about 2 months ago with Breast Cancer and then my sewing teacher who lost her battle with it. The bibs look like this and it's very emotional to see how many people are touched directly and indirectly by Breast Cancer.