How high to jump down without being hurt?

Text ｜ Xinyu

The 3D printing model simulates the force that people bear after entering the water. Picture source: Cornell University

How tall do you dive? An experiment with a 3D printing model studied how high people can jump into the water from the high place without the risk of injuries. Related research results were published in "Scientific Progress" on July 27.

The SUNGHWAN JING team of Cornell University will throw the 3D printing model representing different human postures into the water tank, studying the power that people suffer when jumping into the water. One posture is head facing down, both hands on both sides of the body; the other posture is to raise the hands over the top of the head and touch each other; and the same posture is one leg and one foot touch the water surface first. Each model is equipped with a force sensor and shoots the picture when it drops with a high -speed camera.

In order to determine the unsafe height of diving, the researchers compared their records with the power of physical damage to the human body. They found that the 8 -meter -tall head -to -water tincture, 12 -meter master's priority water, and 15 meters of high -side priority of the water reached the level of injury to the human body.

Jung said that most of the force that affects the body during diving is caused by the displacement of water. This is like you quickly stuffed your fingers into a jar of honey -this liquid will have strong resistance.

However, human beings have successfully jumped from the height of the limit discovered by the study. For example, in 2015, Laso Schaller jumped off from a height of 58.8 meters and broke the record of tactile diving on the foot. Jung said that to complete such extreme jumps without injury, diving people must correctly shrink their muscles and make their bodies harder and tighter.

Nathaniel Jones, the University of Loya, Chicago, said the head and neck were often injured when diving people were wrong, and injuries to the shoulders and lower back were even more common. "Spring athletes dives 100 to 150 times a day, and platform diving athletes jump 50 to 100 times a day. Such frequent diving will make them face more injuries." He said.

Related thesis information:

https://doi.org/10.1126/sciadv.abo5888

"China Science News" (2022-08-01 The second edition of the original title "Scientist calculates the highest safety diving height")

Edit | Zhao Lu

Capture | Zhihai

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