From Sam Miller at ESPN.com on June 27, 2018:
There are two outs, the bases are empty and the batter is 23.
He is, as he steps into the batter’s box, the most exciting player in baseball. As a rookie, he has hit a ball 513 feet in batting practice, thrown a pitch 102.5 mph from the mound and reached a top sprint speed — nearly 30 feet per second — faster than three-quarters of his peers can touch. These are the highlight years, and it feels like just the beginning.
But an athlete’s physical decline begins before most of us notice it, and even the 23-year-old body can do things today that it might not be able to do tomorrow. Fastball speed starts going down in a player’s early 20s, and spin rate drops with it. Exit velocity begins to decline at 23 or 24. An average runner slows a little more than 1 inch per second every year, beginning pretty much immediately upon his debut. It takes a little over four seconds for most runners to reach first base, which means with each birthday, it’s as if the bases were pulled 4 inches farther apart. Triples peak in a player’s early 20s, as does batting average on balls put into play. A 23-year-old in the majors is twice as likely to play center field as left field; by 33, the opposite is true.
Thirty-three feels so far away, but it’s already happening. The 23-year-old’s lean body mass peaked sometime in the preceding five years. His bone-mineral density too. He’s at the age when the body begins producing less testosterone and growth hormone. His body, knowing it won’t need to build any more bone, will produce less energy. Male fertility peaks in the early 20s, the same time as pitch speed and exit velocity. Athleticism is, crudely speaking, about showcasing what a body looks like when it’s ready to propagate a species. The 23-year-old’s machine works as it was designed to. It is undamaged, unsmudged, and every circuit in it is trained to carry on his family’s tradition of survival. When you’re 23, the 32-year-old Mark Trumbo says wistfully, “performance is the only thing holding you back.” To watch a 23-year-old athlete is to see the perfect machine running perfectly.
Read the full article here: http://www.espn.com/mlb/story/_/id/23916211/major-league-baseball-aging-cycle-how-mike-trout-becomes-albert-pujols
Originally published: June 28, 2018. Last Updated: June 28, 2018.