A slam dunk, also simply dunk, is a type of basketball shot that is performed when a player jumps in the air, controls the ball above the horizontal plane of the rim, and scores by putting the ball directly through the basket with one or both hands. It is considered a type of field goal; if successful, it is worth two points. Such a shot was known as a "dunk shot" until the term "slam dunk" was coined by former Los Angeles Lakers announcer Chick Hearn.
I gave myself ten weeks to dunk again. It wasn’t going to be easy: I figured I’d need to add five or six inches to my vertical in order to dunk a regulation basketball. I was in half-decent shape, and at six-foot-three, I had height on my side. But I had a few things other than age working against me—namely feet that had flattened over the years to canoe paddles, and an ankle injury I’d never properly rehabbed.
The simplest method to measure an athlete's vertical jump is to get the athlete to reach up against a flat wall, with a flat surface under his/her feet (such as a gym floor or concrete) and record the highest point he/she can reach flat-footed (the height of this point from the ground is referred to as "standing reach"); fingertips powdered with chalk can facilitate the determination of points touched on the wall. The athlete then makes an effort to jump up with the goal of touching the highest point on the wall that he or she can reach; the athlete can perform these jumps as many times as needed. The height of the highest point the athlete touches is recorded. The difference between this height and the standing reach is the athlete's vertical jump.