Julius Erving revealed a lot about himself in The Doctor, a documentary about his life that ran on NBA TV this week. The New York Times noted that Erving opened up about the deaths of his brother and son and discussed his long path to an NBA title.

The Doctor also revealed that Erving, one of the most influential dunkers in the history of the game, can still throw it down at age 63, more than 25 years after he retired in 1987. Erving's right-hand slam -- shown above -- doesn't look that much different from his dunks in the good old days: he rises powerfully, hangs a bit above the rim, palms the basketball like it's a softball and gracefully completes the slam. Erving competed in the 1985 dunk contest and his entry there doesn't look that much different from this dunk, although he did increase the degree of difficulty in '85 by using a second basketball and rotating.

What does this tell us? For world-class dunkers, throwing down is like riding a bike. Here's a look at some other former NBA players dunking in retirement.

Michael Jordan

Go ahead, get in your jokes about how Bobcats owner Michael Jordan is better than all of the players currently on his roster. Back in 2011, a 48-year-old Jordan easily dunked with his right hand at a "Fantasy Camp" for Bobcats fans. The dunk came -- wait for it -- 23 years after his last dunk contest title in 1988.

Wilt Chamberlain

In this ESPN Classic clip, a retired Chamberlain (age unknown; looks to be somewhere in his 40s) assaults the rim repeatedly against a helpless reporter. Oh, the brutality.

Video via InsideHoops.com.

Marques Johnson

JerseyChaser.com posted a video of former NBA All-Star Marques Johnson jumping over a car at age 55. Yes, there's a slight twist to this one, but the dunk is legit. Johnson told the site that he was "smitten" by Erving's dunking ability as a teenager.

Spud Webb

TotalProSports.com posted this clip of a 47-year-old Spud Webb dunking. A number of YouTube commenters have questioned the clip's authenticity because the 5-foot-6 Webb's feet are not shown during takeoff and the camera shot is pretty tight. Regardless, the whole setup, with Webb taking off his jacket and showing younger players how it's done, is mesmerizing.

Top video via BeyondTheBuzzer.com

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