OK, I'll bite.
I don't do many races that give out medals, but the races that do are usually pretty cool, so I do like to remember them by keeping the medals out rather than stuffed away in a box. I have a really bad memory, and these things serve to jog my memory about cool stuff I've done. I have 2 small shelves (maybe 12-14" wide) in my room that have some of these medals hanging from it. I have medals/trophies from things besides triathlon there too...some plaques from sailing races and various other things that I've raced over the years.
I can't honestly say that I've ever looked at it as bragging--these shelves are not set up plainly displayed for all to see. Most of the medals I have are not even from races that I'd consider my biggest accomplishments--they're finishers' medals rather than some sort of victory medal. Basically...if I wanted to brag about my race resume, this isn't how I would do it. All of the people who would have the occasion to see my collection of medals and trophies have probably seen me race in person--they probably even saw the medals handed to me. They know how fast or slow I am. My little shelf of medals isn't showing them anything about me that they don't already know--everything that's there is there for me.
I'm intrigued by the folks that feel like they need to hide away their medals and whatever else they get from races lest someone think they were bragging or being too self-absorbed. I think it's an interesting commentary on the psyche...sort of in the way that people who are quick to point out a certain type of flaw in other people frequently exhibit that very flaw themselves.
Moral of the story: you can be humble without being ashamed.
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