To answer the original question, there is some real data on aging and running. At least with distance running.
From Christopher McDougall's Born To Run:
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"Then why do so many people hate it?" I asked Dr. Bramble as he came to the end of the story of Louis and the Bushmen. "If we're all born to run, shouldn't all of us enjoy it?"
Dr. Bramble began his answer with a riddle. "This is fascinating stuff," he said. "We monitored the results of the 2004 New York City Marathon and compared finishing times by age. What we found is that starting at age nineteen, runners get faster every year until they hit their peak at twenty-seven. After twenty-seven, they start to decline. So here's the question--how old are you when you're back to running the same speed you did at nineteen?" . . .
" . . . It's sixty-four."
"Are you serious? That's a--" I scribbled out the math. "That's a forty-five-year difference. You're saying teenages can't beat guys three times their age?"
"Isn't it amazing?" Bramble agreed. "Name any other field of athletic endeavor where sixty-four-year-olds are competing with nineteen-year-olds. Swimming? Boxing? Not even close. There's something really weird about us humans; we're not only really good at endurance running, we're really good at it for a remarkably long time. We're a machine built to run--and the machine never wears out."
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You can read it in context here:
This source did a little more digging and found the equivalent line to 19 year olds was 39 or 40, but the point remains the same. It takes a while for age to catch up with a distance runner:
http://www.cognitivedissident.org/2009/08/christopher_mcdougall_born_to.html
So to answer your question, no. Probably not, since 27 is the average "peak" for performance. That's the bad news. The good news is that performance goes down VERY SLOWLY with age after that. so though you probably won't be beating many people in their late 20s, you'll be beating folks half your age for years to come.