A split leap executed by an acro dancer. This is one of several types of leaps found in dance.

Jumping or leaping is a form of locomotion or movement in which an organism or non-living (e.g., robotic) mechanical system propels itself through the air along a ballistic trajectory. Jumping can be distinguished from running, galloping, and other gaits where the entire body is temporarily airborne by the relatively long duration of the aerial phase and high angle of initial launch.

Some animals, such as the kangaroo, employ jumping (commonly called hopping in this instance) as their primary form of locomotion, while others, such as frogs, use it only as a means to escape predators. Jumping is also a key feature of various activities and sports, including the long jump, high jump, and show jumping.

Physics of jumping[link]

Jumping bottlenose dolphin

All jumping involves the application of force against a substrate, which in turn generates a reactive force that propels the jumper away from the substrate. Any solid or liquid capable of producing an opposing force can serve as a substrate, including ground or water. Examples of the latter include dolphins performing traveling jumps, and Indian skitter frogs executing standing jumps from water.

Jumping organisms are rarely subject to significant aerodynamic forces and, as a result, their jumps are governed by the basic physical laws of ballistic trajectories. Consequently, while a bird may jump into the air to initiate flight, no movement it performs once airborne is considered jumping, as the initial jump conditions no longer dictate its flight path.

Following the moment of launch (i.e., initial loss of contact with the substrate), a jumper will traverse a parabolic path. The launch angle and initial launch velocity determine the travel distance, duration, and height of the jump. The maximum possible horizontal travel distance occurs at a launch angle of 45 degrees, but any launch angle between 35 and 55 degrees will result in ninety percent of the maximum possible distance.

Muscles (or other actuators in non-living systems) do physical work, adding kinetic energy to the jumper's body over the course of a jump's propulsive phase. This results in a kinetic energy at launch that is proportional to the square of the jumper's velocity. The more work the muscles do, the greater the launch velocity and thus the greater the acceleration and the shorter the time interval of the jump's propulsive phase.

A dog jumping from a stationary position

Mechanical power (work per unit time) and the distance over which that power is applied (e.g., leg length) are the key determinants of jump distance and height. As a result, many jumping animals have long legs and muscles that are optimized for maximal power according to the force-velocity relationship of muscles. The maximum power output of muscles is limited, however. To circumvent this limitation, many jumping species slowly pre-stretch elastic elements, such as tendons or apodemes, to store work as strain energy. Such elastic elements can release energy at a much higher rate (higher power) than equivalent muscle mass, thus increasing launch energy to levels beyond what muscle alone is capable of.

A jumper may be either stationary or moving when initiating a jump. In a jump from stationary (i.e., a standing jump), all of the work required to accelerate the body through launch is done in a single movement. In a moving jump or running jump, the jumper introduces additional vertical velocity at launch while conserving as much horizontal momentum as possible. Unlike stationary jumps, in which the jumper's kinetic energy at launch is solely due to the jump movement, moving jumps have a higher energy that results from the inclusion of the horizontal velocity preceding the jump. Consequently, jumpers are able to jump greater distances when starting from a run.

Anatomy[link]

A bullfrog skeleton, showing elongate limb bones and extra joints. Red marks indicate bones substantially elongated in frogs, and joints that have become mobile. Blue indicates joints and bones that have not been modified, or are only somewhat elongated.

Animals use a wide variety of anatomical adaptations for jumping. These adaptations are exclusively concerned with the launch, as any post-launch method of extending range or controlling the jump must use aerodynamic forces, and thus is considered gliding or parachuting.

Aquatic species rarely display any particular specializations for jumping. Those that are good jumpers usually are primarily adapted for speed, and execute moving jumps by simply swimming to the surface at a high velocity. A few primarily aquatic species that can jump while on land, such as mud skippers, do so via a flick of the tail.

Limb morphology[link]

In terrestrial animals, the primary propulsive structure is the legs, though a few species use their tails. Typical characteristics of jumping species include long legs, large leg muscles, and additional limb elements.

Long legs increase the time and distance over which a jumping animal can push against the substrate, thus allowing more power and faster, farther jumps. Large leg muscles can generate greater force, resulting in improved jumping performance. In addition to elongated leg elements, many jumping animals have modified foot and ankle bones that are elongated and possess additional joints, effectively adding more segments to the limb and even more length.

Frogs are an excellent example of all three trends: frog legs can be nearly twice the body length, leg muscles may account for up to twenty percent of body weight, and they have not only lengthened the foot, shin and thigh, but extended the ankle bones into another limb joint and similarly extended the hip bones and gained mobility at the sacrum for a second 'extra joint'. As a result, frogs are the undisputed champion jumpers of vertebrates, leaping over fifty body lengths, a distance of more than eight feet.^[1]

Power amplification through stored energy[link]

Grasshoppers are known to use elastic energy storage to increase jumping distance. As noted above, power output is a principal determinant of jump distance, but physiological constraints limit muscle power to approximately 375 Watts per kilogram of muscle.^[2] To overcome this limitation, grasshoppers anchor their legs via an internal "catch mechanism" while their muscles stretch an elastic apodeme (similar to a vertebrate tendon). When the catch is released, the apodeme rapidly releases its energy. Because the apodeme releases energy more quickly than muscle, its power output exceeds that of the muscle that produced the energy.

This is analogous to a human throwing an arrow by hand versus using a bow; the use of elastic storage (the bow) allows the muscles to operate closer to isometric on the force-velocity curve. This enables the muscles to do work over a longer time and thus produce more energy than they otherwise could, while the elastic element releases that work faster than the muscles can. The use of elastic energy storage has been found in jumping mammals as well as in frogs, with commensurate increases in power ranging from two to seven times that of equivalent muscle mass.^[3]

Classification[link]

One way to classify jumping is by the manner of foot transfer.^[4] In this classification system, five basic jump forms are distinguished:

• Jump — jumping from and landing on two feet
• Hop — jumping from one foot and landing on the same foot
• Leap — jumping from one foot and landing on the other foot
• Assemble — jumping from one foot and landing on two feet
• Sissonne — jumping from two feet and landing on one foot

Leaping gaits, which are distinct from running gaits (see Locomotion), include cantering, galloping, and pronging.^[5]

Devices and techniques for enhancing jumping height[link]

The height of a jump may be increased by using a trampoline or by converting horizontal velocity into vertical velocity with the aid of a device such as a half pipe.

Various exercises can be used to increase an athlete's vertical jumping height. One category of such exercises—plyometrics—employs repetition of discrete jumping-related movements to increase speed, agility, and power.

References[link]

See also[link]

Look up jumping in Wiktionary, the free dictionary.

• List of jumping activities
• Video game jumping: bunny hopping, rocket jumping, strafe-jumping, trickjump

Felix Baumgartner (born 20 April 1969 in Salzburg, Austria) is an Austrian skydiver and a BASE jumper. He is renowned for the particularly dangerous nature of the stunts he has performed during his career. Baumgartner spent time in the Austrian military where he practiced parachute jumping, including training to land on small target zones.

Biography[link]

He was born on 20 April 1969 in Salzburg, Austria.^[1]

In 1999 he claimed the world record for the highest parachute jump from a building when he jumped from the Petronas Towers in Kuala Lumpur, Malaysia.^[2]

On 31 July 2003, Baumgartner became the first person to skydive across the English Channel using a specially made fibre wing.^[3]

Baumgartner set the world record for the lowest BASE jump ever, from the hand of the Christ the Redeemer statue in Rio de Janeiro.^[4]

He became the first person to BASE jump from the completed Millau Viaduct in France on 27 June 2004^{[citation needed]} and the first person to sky dive onto, then BASE jump from, the Turning Torso building in Malmö, Sweden on 18 August 2006.^[5]

On 12 December 2007 he became the first person to jump from the 91st floor observation deck, then went to the 90th floor (about 390 m (1,280 ft)) of the then tallest completed building in the world, Taipei 101, Taipei, Taiwan.^[6]

[edit] Red Bull Stratos

In January 2010, it was reported that Baumgartner was working with a team of scientists and sponsor Red Bull to attempt the highest sky-dive on record.^[7] Baumgartner was going to make the 120,000 ft (36,600 m) jump from a capsule suspended from a balloon filled with helium, intending to become the first parachutist to break the sound barrier; the feat was scheduled to take place sometime in 2011.^[8][9][10] Joseph Kittinger, who holds the records Baumgartner is attempting to break, was advising Baumgartner during the "Stratos" mission in the hopes of getting scientific data on next-generation full pressure suits.^[7][11] However, on October 12, 2010, Red Bull announced it was placing the project on hold after Daniel Hogan filed a lawsuit in California Superior Court in Los Angeles, California in April, claiming he had originated the idea of the parachute dive from the edge of space in 2004 and that Red Bull had stolen the idea from him.^[12][13] The lawsuit was resolved out of court in June 2011^[14] and on 5 February 2012, The Daily Telegraph reported that the project would be resumed.^[15]

On 15 March 2012 he completed the first of two test jumps from 71,581 feet (21,818 m). During the jump he spent approximately three minutes and 43 seconds in free fall, reaching speeds of more than 360 miles per hour (580 km/h), before opening his parachute. In total, the jump lasted approximately eight minutes and eight seconds and Baumgartner became only the third person to safely parachute from a height of over 13.5 miles (21.7 km).^[16]

See also[link]

• Michel Fournier, who has been working on a 25 mile jump for several years.^[17]
• Joseph Kittinger, world record holder for skydiving from 102,800 ft
• Yves Rossy, the first man to cross the English Channel using a jet-powered wing

References[link]

External links[link]

• Official website
• Red Bull Stratos Project
• Felix Jumping from the Christ Redemeer - Rio de Janeiro - Brazil

External media
	Felix Baumgartner