Never let your body exceed these seven limits

As people's living standards improve, more and more people are beginning to pursue a more exciting life, and many people have begun to challenge their own limits, but how much do you know about the limits of the human body? If you are not careful, fatal phenomena may occur. Do you know what the fatal limits of the human body are? Do you know what the limits of the human body can bear? Today, the Popular Health Network will introduce you to the knowledge about extreme sports that are harmful to your health. Friends who are interested, come and have a look.

1. Sound Limit

Each of us has a certain limit to our hearing. If the sound is too loud, it will cause our eardrums to rupture, which may cause people to become deaf. Therefore, we must pay attention to the limit of human hearing. The limit of testing human hearing is calculated based on decibels.

Volumes exceeding 40 decibels will interfere with sleep, and being in an environment of 60 decibels for a long time will make people anxious; 80 decibels will make people lose their appetite; above 90 decibels will increase blood pressure and speed up heartbeat; sounds of 125 decibels will give people headaches.

Volumes above 130 decibels (the sound of a jet engine) can cause ear pain even for a short period of time; and levels above 150 decibels can cause rupture of the eardrum, inner ear bleeding, and damage to the nerve cells in the inner ear.

If a person hears a 200-decibel sound within a 20-kilometer range, the pressure wave can damage their lungs, causing outside air to enter the bloodstream and cause a fatal pulmonary embolism.

2. Blood loss limit

We all know that human blood plays a certain role in the body. A large amount of ischemia may lead to death. Therefore, the amount of human blood also has a certain limit. Generally speaking, the amount of blood in a healthy adult's body is approximately between 3.8 and 5.6 liters.

If you lose more than 15% of your blood volume, your pulse will race and you may feel dizzy and cold. If 40% of the blood volume is lost, this will affect the blood flow back to the atrium, causing symptoms of tachycardia.

The human body's maximum blood loss at one time is 1.9 to 2.8 liters, which accounts for about 50% of the total blood volume. If the human body is in a condition of chronic blood loss, the minimum remaining blood volume is 1 liter, which means losing 78% of the body's blood volume.

3. Human body low temperature limit

The core body temperature of a person is 37 degrees Celsius. Generally speaking, an external temperature of around 20 degrees Celsius can cause the body temperature to drop.

Once the body temperature drops to 36 degrees Celsius, a person's reaction and judgment abilities will be weakened; when it drops to 35 degrees Celsius, it will be difficult to walk; when it drops to 33 degrees Celsius, a person will lose his mind; at 30 degrees Celsius, a person will lose consciousness; and when the core body temperature reaches 24 degrees Celsius, the heart will stop beating.

In 2001, a toddler survived temperatures as low as -20 degrees Celsius. Her heart stopped beating for two hours and her body temperature was only 16 degrees Celsius.

4. Human body temperature limit

The upper limit of a normal human axillary temperature is usually 37.4 degrees Celsius. If you have a fever, it will usually not exceed 42 degrees Celsius.

But in 1980, the temperature in Atlanta, Georgia, USA was 32.2 degrees Celsius. Willie Jones, 52, was admitted to Atlanta's Grady Memorial Hospital due to heat stroke. At that time, his body temperature reached a record high of 46.5 degrees Celsius, and it took 24 days for the fever to subside completely.

5. Ambient temperature

The human body can withstand a high temperature of 71 degrees Celsius for 1 hour; a high temperature of 82 degrees Celsius for 49 minutes; a high temperature of 93 degrees Celsius for 33 minutes; and a high temperature of 104 degrees Celsius for 26 minutes.

The highest ambient temperature that the human body can withstand is 116 degrees Celsius.

6. Altitude Limit

If people stay at an altitude of more than 5,000 meters for a long time, they will suffer from muscle atrophy, a significantly increased risk of fluid accumulation in the lungs and brain, and reduced male fertility.

High altitude can cause hypoxia in the human body, and the first reaction of altitude sickness is headache and dizziness. If people stay at an altitude of more than 5,000 meters for a long time, they will suffer from muscle atrophy, a significantly increased risk of fluid accumulation in the lungs and brain, and reduced male fertility; at an altitude of more than 7,500 meters, severe lack of oxygen can lead to loss of consciousness and even death.

Most people can gradually adapt to the plateau environment after a period of time. But if ordinary people are suddenly sent to the top of Mount Everest, which is 8,848 meters above sea level, without going through a period of adaptation, they will be at risk of death.

So, what is the upper limit of the height that humans can endure? In fact, the height of the top of Mount Everest is very close to the limit that humans can endure. Mike Grocott, who studies the physiological effects of altitude at the University of Southampton in the UK, believes that the limit should be around 9,000 meters.

7. How long can a person survive in a vacuum?

Astronauts will die if they are suddenly exposed to a vacuum for 30 to 40 seconds. When external pressure decreases, bubbles form in the blood and the lungs can be damaged within minutes. As nitrogen is removed from the blood, the nervous system can be damaged within hours.

A sudden drop in pressure is fatal to the human body: the air that seeps into the lungs explodes in a matter of seconds. If the near-vacuum state is entered in a more appropriate manner and with medical supervision, a person may be able to survive for up to 1 minute.