This is from “Born to Run” by Christopher McDougall.
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?
The answer: 64!