Beyond the Boxscore’s Jeff Zimmerman recently studied the aging curves for big-league hitters. Among his findings:
Starting at 33, hitters from more recent years (1980–2010) aged slower than ballplayers from earlier eras (1950–79), which Zimmerman suggested was thanks in part to advances in medicine.
“The age that players peak changed from 25 to 26 when comparing the two 30-year intervals.”
“Young-old players* peak at age 25, which is one year earlier than the general population.”
Fast players age extremely well from their peaks at 26 to 31, then continue to outperform their peers through their mid-30s.
* “These players exhibit power at an early age with high number of walks and strikeouts.”