Find the limit of endurance of the human body

Do you know the limits of your body with temperature, pressure, night, electric shock or loudness, etc.?

We have heard about the miraculous surviving stories of people on the beach for months, or falling from the 10th floor of a building, even a bullet shot through the brain. These stories show great endurance of the human body. However, we still have our own limits.

'Rule 3' is one of the famous theories about the limits of the human body's tolerance, that is, we cannot hold our breath for more than 3 minutes, cannot stop drinking for more than 3 days and cannot help it. eat more than 3 weeks. Besides there are many other human limitations that we have not been able to discover, as you can climb to any limit before you die from asphyxiation, or you can dive to how deep before you die. Because of the water pressure, we can move at maximum speed before being torn into many parts.

How many days can we not sleep?

Previously, there have been reports of an airplane pilot becoming delirious after 3-4 days of sleeplessness and causing the fighter to crash straight into a cliff, or the impact of a similar lack of sleep. like drunk for truck drivers. This shows great harm from lack of sleep. However a 17-year-old boy named Randy Gardner once set a Guinness record by not sleeping for 11 days.

Even so, there was a case of a Chinese man who died after 11 days of not sleeping because he saw all the Euro Cup matches. But he also drank alcohol and smoked during those 11 days, causing the determination of the cause of death due to lack of sleep or not much difficulty. For ethical reasons, scientists cannot conduct similar experiments in the laboratory.

Therefore, scientists at the University of Chicago conducted an experiment on rats. They make them unable to sleep and record changes in the body and brain waves. As a result, all tested mice were unable to live for more than 20 days, and their bodies experienced excessive calorie burning while not being active and still eating normally.Scientists also predict that the human body cannot tolerate more than 15 days without sleep , although still eating normally and not being heavy.

Maximum acceleration can withstand?

The current flight speed record is 11,270km / h from NASA X-43A, demonstrating that our bodies can withstand very high speeds. However, acceleration is a big difference, a large velocity change in a short period of time can cause a tremendous force. It can crush our bodies and hurt internal organs.

NASA and military scientists have had to study this issue very carefully, in order to design spacecraft and fighters, to ensure the pilots' safety with great pressure when accelerating with acceleration. great. According to studies, the human body can withstand the acceleration of about 4-8G vertically from head to toe , before our blood is cornered to one side (1G is gravity, gravity Earth's is about 9.8m / s ² ).

In the horizontal direction, our bodies can withstand about 14G before the internal organs are damaged. While the human body can withstand the greatest acceleration is in the direction from the front to the back of the body, because the chest protects the internal organs. A 1950 military experiment with a rocket-mounted sleigh showed that humans could withstand acceleration of up to 45G in this direction. That means the car accelerates from 0 - 1000km / h in just 1s. Scientists estimate our bodies will not be able to withstand more than 50G , at which time the internal organs will be crushed by great pressure.

Body temperature tolerance

According to a NASA 1958 report, humans can live in conditions of ambient temperature ranging from 4 to 35 degrees Celsius. The maximum temperature can be pushed up if the air humidity is low, because of the amount of clear water. The lower gas the body will easily sweat more and help reduce the body's temperature.

Our bodies have stable body temperature at 37 degrees Celsius, but if the ambient temperature reduces body temperature, it will cause very significant effects. If your body temperature drops to 35 degrees C, your limbs will shake and it's hard to move. At 32 degrees C, most people will lose consciousness, the body will give up trying to maintain body temperature. The breath decreases and the heart rhythm disturbs when the temperature is 28 degrees C. And when the body temperature is only 20 degrees C, the heart stops beating. However, there was a case where a girl walked in the weather -20 degrees C and her body temperature was only 16 degrees Celsius but still saved.

It seems that we are better able to withstand cold than heat.The body's highest temperature that can sustain life is 42 degrees Celsius , because at this temperature the body's essential proteins begin to break down. Compared to the outside temperature, even fully equipped firefighters can only withstand the ambient temperature up to 93 degrees C.

Climbing and diving on the ocean floor

The higher the atmospheric pressure, the lower the air pressure and the more dilute the air is, the less oxygen will be reduced. We will die when the oxygen concentration in the air drops below 11%. According to calculations by scientists, we will not be able to breathe without oxygen tanks on an altitude of about 7,900m.

Meanwhile, if we dive to the bottom of the sea without special equipment, we will suffer from lack of oxygen and great pressure of water. Usually a person can dive down to about 18m. But the world record records the greatest depth that humans can dive down to 85m.

And other limits of the body

A normal person has between 3.8 and 5.6 liters of blood. You can lose about 15% of blood in your body without any effect. However, if you lose a larger amount of blood, you will feel dizzy, heart palpitations. When you lose about 40% of your blood, your blood pressure is too low to push blood away and your heart starts to beat. If you exceed 50%, your heart will be unbearable and will lead to death.

More than 60% of our bodies are water, so water is very important. However, drinking too much water is not a good thing, it can even cause us to lose our lives. According to doctors, 10L of water is the maximum amount of water you can drink within 1 hour without diluting the electrolytes in your body causing the muscles to twitch and possibly die.

The magnitude of the sound is measured in decibels. About 30dB is the loudness in quiet villages, while 120dB is the loudness that you can hear at rock shows.The biggest sound we can hear is about 160dB , if the sound is greater than this threshold, it can cause the eardrum to tear. When the sound is 200dB, sound waves with high pressure can even break the lungs, pushing air into the color vessels, causing the blood vessels to die.

Death from electric shock is a very common cause. The cause of death is not the large voltage, but the current (amperes) . A current of about 1mA can cause a bit of numbness, while a 200mA current is enough to take away our lives. The resistance of human skin varies from 1,000 Ohms (wet skin) to 100,000 ohms (dry skin), so the corresponding voltage level can be deadly 200V (wet skin) and 20,000V (dry skin) . In fact, only 10% of lightning strikes cause death.