The vertical jump is one of the most explosive physical movements executed in sport. In a number of sports, the higher the athlete is able to jump, the greater the prospects of success in that discipline. Basketball and volleyball are the two most prominent examples of sports where that correlation is plain. The jumping ability of an athlete is also an indicator of overall athletic ability, as there is a clear relationship between the ability to jump and the running speed that the athlete will develop over short distances. The National Football League, where prospective players are subjected to various physical tests, requires every player to be tested for both vertical leaps and 40-yd (37 m) sprints, irrespective of the position played.

Not so long ago, I played the worst basketball game of my life. I missed layups, turned over the ball, allowed my opponent free reign to the hoop. It was dark. As I slumped on the sidelines after the game, I realized how far I’d fallen from my prime a decade ago. Back then, I could dunk; now, at 33, I could barely curl my fingers over the rim. My game had regressed to hovering around the arc jacking threes. The last time I dunked a basketball, Michael Jordan was a Washington Wizard and people still listened to Coldplay.
If anything came to surprise me about this journey, it was the sheer volume of physical pain involved. I had taken on impressive physical feats before. I had run a sub-3:30 marathon back in 2003 (my first and only attempt) after put­ting in the hundreds of training miles required. I’d done some of the most grueling weight training on offer, most of it either on the beach or at The Yard, a nearby temple of athletic performance where Maria Sharapova, Kobe Bryant and Tom Brady, among many others, have kneeled with exhaustion. But the physical toll of trying to dunk made the marathon and the semipro football and the parenting and everything else I’d ever attempted seem like mere rubber band snaps to the wrist. The lifting didn’t hurt as much as the jumping, the banging of my quadragenarian appendages into the ground, taking off and landing 50 to 200 times a day. My legs never got used to this bludgeoning, never got better at recovering from it, despite my daily foam-rollering, stretching, icing and hydrating. Even on my off days, a quick game of tag with my kids or a bike ride to the park meant daggers in my thighs and a gait like Fred Sanford’s.
The days and jumps and deadlifts and calf raises rolled on, rep by rep, protein shake by protein shake. Six months became seven, then eight. To protect my right hand, I began wearing a canvas gardening glove with the fingers cut off. It soon became stained with blood—the equivalent of Curt Schilling’s bloody sock, but with one-millionth the significance. The rims where I toiled belonged to me now, such that I barely noticed the toddlers wobbling nearby, the skateboarders swirling around me as day turned to dusk, the elderly couple ambling arm in arm, looking for all the world like my wife helping me to the shower on the morning after a double day.
The things I had going for me: an understanding spouse; a modicum of foot speed and leaping ability, flashed during the occasional Motrin-supported­ pickup game; proximity to one of the best training centers in the world; and, again, an understanding spouse. The forces working against me made for a longer list and included (but were far from limited to) my average hand size and arm length, a lower-back injury that I suffered while playing semipro football in 2009 and my age. I was 42.
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.
In the tradition of New Year’s resolutions and the like, you can give yourself a year. I certainly didn’t want to give myself more than a year, because after a year I knew I would grow tired of it, and my body would start to get quite unhappy with me. But I would recommend to someone that they give it a go for at least six months. It’s also a way of just getting yourself in fantastic shape. I mean, trying to dunk a basketball in itself is awesome. It’s really great to be able to dunk a basketball, to get yourself higher up than you thought possible. But the process of getting yourself in that kind of position is itself rewarding.
To begin, go up without a ball first. This will give you a great idea of where you’re at and just how close you are to being able to dunk. For beginners, you should focus on dunking with one hand. Your other hand should stay by your side to balance your body while you’re in the air. The two-handed dunk is awesome, but is surprisingly more of an advance dunk and should be an approach you build up to as you work on your dunking.
Stand with your feet shoulder-width apart. Keeping your back straight, bend at your knees and hips as if you are attempting to sit in a chair until your thighs are parallel with the floor. Simultaneously extend your arms straight out in front of you. From this position jump up, straighten your legs and swing your arms back down to the side of your body. Repeat 25 jumping squats in a row for three sets with a 1-minute break between sets.
Because of the possible combinations of starting and finishing hands, and raised-legs, there are many variations on the basic under-the-legs dunk—more so than any other.[17] For example, in a 1997 French Dunk contest, Dali Taamallah leapt with his right leg while controlling the ball with his left hand, and once airborne he transferred the ball from his left hand, underneath his right leg to his right hand before completing the dunk.[18] NBA star Jason Richardson has also pioneered several notable variations of the between-the-legs including a lob-pass to himself[19] and a pass off of the backboard to himself.[20] Independent athlete Shane 'Slam' Wise introduced a cuffed-cradle of the ball prior to initiating the under the leg transfer and finishing with two-hands.[21] While a number of players have finished the dunk using one- or two-hands with their backs to the rim, perhaps the most renowned variant of the dunk is the combination with a 360°, or simply stated: a 360-between-the-legs. Due to the athleticism and hang-time required, the dunk is a crowd favorite and is heralded by players as the preeminent of all dunks.[citation needed]
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.