From a Wall Street Journal story by Clare Ansberry headlined “Here’s When We Hit Our Physical and Mental Peaks”:

When are we our fastest, strongest and most creative?

Elite swimmers peak in their early 20s, powerlifters peak at 35 and equestrians later still, on average. Creativity peaks either very early in our careers or later, depending on how we think. Our ability to quickly absorb facts reaches its zenith in our late teens, while our vocabulary skills crest in our sixth decade.