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There are many kinds of sports shoes, but the basic principles are similar. Their main function is to absorb the impact from the ground. When a person's running speed reaches 6 meters per second, the load on the soles of his feet is about 4 times of his weight, which increases to 7 times in high jump and long jump. In the triple jump, his feet directly collided with the hard ground twice, and the peak impact force could reach more than 20 times his weight. Strong vibrations will spread to his ankles, knees, hips, spine and brain.

Sports shoes put a material with high "compression flexibility" at the heel to make it absorb impact kinetic energy through maximum deformation. Some sports shoes put rubber columns and air cushions on the soles as shock-absorbing springs under the automobile chassis.

The second function of sports shoes is that they can still be used. Polyurethane and other microcellular foam materials in the sole have strong elasticity. When the sole is deformed and reduced under pressure, the absorbed and stored energy can be released and returned to the sole. In the cycle of pedaling and stretching, it is like stepping on a miniature "springboard". The technical essence here is to find a balance between the elasticity and stability of shoes, so as to obtain the ideal recoil without losing the precise sense of space and the "down-to-earth" hard support.

The third function of sports shoes is anti-skid. The friction of sole is determined by the normal force between sole and ground, friction coefficient and contact area. Microscopically, because the ground is uneven, there is often only limited "point contact" with the sole. The soles with high friction coefficient and high ductility can produce elastic deformation on the ground in scraggy and increase the contact surface, which is called "grip". Modern spiked shoes are made of composite materials such as nylon and polyurethane, and the number and position of spiked shoes can be adjusted and changed by people and places. A large number of sports shoes have replaced spikes with different rows of ridges. As for the pattern of the sole, it is ever-changing, which brings the difference of friction in different directions and meets the needs of different sports.

As for the correction of foot shape and movement by the torsion system of sports shoes, the support of shoes facing ankles, and the ventilation and moisture absorption in shoes through the "breathing" function of pores are all remarkable designs. Almost all different sports have their own special shoes, and the technology involved in sports shoes is a very complicated knowledge.