Jumping

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 an locomotion, while others, such as frogs, use it only as a means to escape predators.

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.

To circumvent this limitation, many jumping species slowly pre-stretch elastic elements, such as tendons or apodemes, to store work as strain energy.

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.

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.

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.

[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).

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.

It has been shown in research that children who are more physically active display more proficient jumping (along with other basic motor skill) patterns.

Jumping development is more easily identifiable in children rather than adults due to the fact that there are less physical differences at a younger age.