When performing a vertical jump, the athlete exerts force at the low back, hip, knee, and ankle joints. The spine flexes as the athlete squats downwards, and then is extended by the spinal erectors over the course of the jump. The hip extensors (gluteus maximus, hamstrings, and adductor magnus) work to move the trunk and the thigh apart, which pushes the torso up and backwards. Meanwhile, the knee extensors (quadriceps) contract to extend the knee, and the calf muscles contract to move the shin backwards, towards the vertical.
The baseline dunk is an approach-modifier of any dunk type in which the player approaches the basket along the court-boundary (baseline) which runs parallel with the backboard. In the game setting, the dunk often comes as the result of a pass, creating an assist opportunity for a teammate. In the contest, the baseline approach may be used as a means of convenience, facilitating a particular dunk type (e.g., passes bounced off the side of the backboard or its padding) or to increase the difficulty of a dunk type in hopes of meriting higher scores.
Of course, these forces increase linearly with increasing body weight. Therefore Olympic high-jumpers are usually build more like marathon runners and less like football players. Every unnecessary pound adds to the forces during take-off, and at some point the muscles and tendons of the jumping leg are just not strong enough any more to support all the weight.
The between-the-legs dunk was popularized by Isaiah Rider in the 1994 NBA slam dunk contest, so much so that the dunk is often colloquially referred to as a "Rider dunk" — notwithstanding Orlando Woolridge's own such dunk in the NBA contest a decade earlier. Since then, the under-the-leg has been attempted in the NBA contest by a number of participants, and has been a staple of other contests as well. Its difficulty — due to the required hand-eye coordination, flexibility, and hang-time — keeps it generally reserved for exhibitions and contests, not competitive games. Ricky Davis has managed to complete the dunk in an NBA game, but both he and Josh Smith have botched at least one in-game attempt as well.
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.
From the Department of Intensive Care, Erasme University Hospital (D.D.B., A.B., J.-L.V.); the Department of Intensive Care, Brugmann University Hospital, Université Libre de Bruxelles (J.D., P.G.); and the Department of Intensive Care, Centre Hospitalier Etterbeek Ixelles (D.C.) — all in Brussels; the Department of Intensive Care, Centre Hospitalier Universitaire de Charleroi, Charleroi, Belgium (P.B., P.D.); the Department of Medicine III, Intensive Care Unit 13H1, Medical University of Vienna, Vienna (C.M.); and the Department of Anesthesia and Critical Care, Rio Hortega University Hospital, Valladolid, Spain (C.A.).
In the 2011 NBA contest, Los Angeles Clippers power-forward Blake Griffin completed a self-pass off of the backboard prior to elbow-hanging on the rim. A number of other variants of the elbow hang have been executed, including a lob self-pass, hanging by the arm pit, a windmill, and over a person. Most notable are two variations which as of July 2012, have yet to be duplicated. In 2008, Canadian athlete Justin Darlington introduced an iteration aptly entitled a 'double-elbow hang', in which the player inserts both forearms through the rim and subsequently hangs on both elbows pits. Circa 2009, French athlete Guy Dupuy demonstrated the ability to perform a between-the-legs elbow hang; however, Guy opted not to hang on the rim by his elbow, likely because the downward moment could have resulted in injury.
Johan Norberg, del Instituto Cato critica el libro diciendo que "El análisis de Klein es erróneo y fuera de lógica en prácticamente a todos los niveles". Norberg encuentra fallas en aspectos específicos de los análisis, como las protestas de Tiananmen de 1989, que, afirma, no aplastaban a la oposición a las reformas pro-mercado, sino que en realidad causó la liberalización de residencia durante años.20
On the basis of the results of the SOAP study,3 which showed a rate of death of 43% among patients receiving dopamine and a rate of 36% among patients receiving norepinephrine, we estimated that with 765 patients in each group, the study would have 80% power to show a 15% relative difference in the rate of death at 28 days, at a two-sided alpha level of 0.05.
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.