It takes a higher vertical leap to get both hands up to the rim versus just one (and don’t forget, you’ll be holding a basketball as well), so if you’re cutting it close, try for a one-handed jam. Being able to palm the ball will obviously help, but it’s not totally necessary; just make sure you keep the ball in both hands until you leave the floor so you don’t lose it.
A forceful, dramatic move, as in That indictment was a slam dunk if ever there was one. This expression is also often put as a verb, slam-dunk, meaning "make a forceful move against someone," as in This is a great chance for us to slam-dunk the opposition. The idiom comes from basketball, where it refers to a dramatic shot in which the ball is thrust into the basket from above the rim. It was transferred to other activities from about 1980 on.
In 2004, as a high school senior, Candace Parker was invited to participate in the McDonald's All-American Game and accompanying festivities where she competed in and won the slam dunk contest. In subsequent years other women have entered the contest; though Kelley Cain, Krystal Thomas, and Maya Moore were denied entry into the same contest in 2007. Brittney Griner intended to participate in the 2009 McDonald's Dunk Contest but was unable to attend the event due to the attendance policy of her high school. Breanna Stewart, at 6'3" (191 cm), Alexis Prince (6'2"; 188 cm), and Brittney Sykes (5'9"; 175 cm) competed in the 2012 contest; Prince and Sykes failed to complete their dunks, while Stewart landed two in the first round but missed her second two attempts in the final round.
Before takeoff, or at the onset of the jump, the ball is brought to the abdomen and then the windmill motion is started by moving the ball below the waist according to the length of the player's fully extended arm. Then following the rotation of the outstretch arm, the ball is moved in a circular motion, typically moving from the front towards the back, and then slammed through the rim (from the profile view of a player facing the basket, the windmill motion most generally appears clockwise). Although, due to momentum, many players are unable to palm the ball through the entire windmill motion, the dunk is often completed with one-hand as centripetal force allows the player to guide the ball with only their dunking hand. In some instances sticky resins or powders may be applied to the palm, these are thought to improve grip and prevent loss of possession. Amongst players, subtle variations in the direction of the windmill depend on bodily orientation at takeoff and also jumping style (one-foot or two-feet) in relation to dominant hand.
Among the hundreds of lessons I learned during my youngest child’s first year of life was this: If you earnestly pursue dunking after your athletic peak years of 18 to 30, give or take, it can be done. You can enjoy what it feels like to dunk. You can even feel it more purely than I did, maybe without needing a lob from a friend, and hopefully without all the hand damage. But you should expect a long, frustrating, demeaning war of attrition that pits mind, body, spirit against the most oppressive, unrelenting opponent of them all: gravity. The sun rises and sets, the tides creep in and out—even taxes and death seem negotiable nowadays—but gravity remains constant, forever pounding our shoulders, stooping us shorter as we grow gray, never letting up—no matter what NASA tweets.