LeBron James has lost significant weight this summer.
NBA players losing weight has been one of the most interesting trends of the offseason.
These three guys were all drafted in 2003. They were among the five best players in the league for a decade. They were on the Olympic team that restored USA Basketball to dominance. They were at the forefront of every major and minor NBA trend you can think of — from the rise of the superteam in free agency, to the widespread use of the "stretch-4" on the court, to the explosion of the outrageous NBA fashion off the court.
Now, all at once, they're slimming down.
And to answer why they're slimming down, you just have to look at Kobe Bryant.
In summer 2007, Kobe was at the exact point in his career that LeBron is now. He was 29 years old and going into his 12th NBA season. He was also coming off the two best statistical seasons of his life.
That summer he lost 20 pounds. It worked. Over the next three years he won two titles, made the NBA Finals every year, averaged 27 points per game, and missed only nine of 246 regular-season games.
NBA players typically fall apart when they hit age 30. A study in the book "Stumbling on Wins" found that players decline 11% in year-over-year performance from age 29 to 30, 15% from 30 to 31, 22% from 31 to 32, and 35% from 32 to 33.
That wasn't the case with Kobe. While he never returned to the superhuman statistical heights he reached in 2005-2006, he maintained the statistical profile of an elite player from age 29 to 34 — a period in which most NBA players rapidly decline.
He was slimmer at 34 than he was at 28:
Lisa Blumenfeld/Streeter Lecka/Getty Images
The takeaway was simple: You can extend your prime if you change your body shape once you hit your 30s.
I told him I thought the thing that really helped me out, I dropped some weight. I told him he should probably measure it himself, see if that's something he needs to do himself. As we get older, our metabolism slows, we quietly become a little heavy.
Kobe lost an additional 16 pounds in summer 2012, when he played in the Olympics alongside LeBron, Carmelo, and Wade, among others.
He isn't the only example of an older player finding success after losing weight. Tim Duncan lost 20 pounds in 2012, and he has enjoyed an unusually long third act to his career. Ray Allen, who was picked in the same draft as Kobe, went on a paleo diet last summer and was reportedly the most in-shape player at the Heat's training camp.
But the NBA has a long tradition of imitation, where the rest of the league follows the lead of the perceived Best Player In The World. Just as Kobe borrowed liberally from Michael Jordan's repetoire both on and off the court, the current generation is doing as Kobe does when it comes to late-career body maintenance.
It takes extreme dedication to lose significant weight at a point in your career in which you have already earned over $100 million and are on the top of the world. Kobe, with one of the most vigorous work ethics of any athlete ever, had that dedication, and it helped him play longer than most NBA players.
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