It seems like a lot of people here ran in college and just kept going from there. Others might not have started running before age 40. What's your deal, and how fast did you get?
I'm 28, and I've only recently started to take running seriously. I know I'm still getting newbie gains and will get a lot faster pretty easily, but it's kind of sad to think that I "wasted" most of my 20s - your peak years physically - either not running or being a hobby jogger.
I was injured for much of 2013, but I've built up to 50-60 mile weeks with workouts. Just ran a 3-minute 10k PR, so I'm excited about the possibilities for the future.
PRs:
8k: 29:50 (Nov 2013, age 28)
10k: 36:55 (Feb 2014, age 28)
Marathon: 3:09:xx (crash and burn, Oct 2012, age 27)