The core content of this hot search is sauce purple:
90% of heat dissipation is radiation heat dissipation, and only 10% or less is exchanged with air.
You don’t need to bask in the sun, you just stay there, you can radiate out, and you can lose weight.
Then, many onlookers and fat friends said, “This is counterintuitive, but the theory is really like this”:
What the hell is this amazing set?scientific weight lossDafa?
Lose weight by stripping: 120 calories in 1 hour
In fact, this “stripping weight loss method” is based on physicsblack body radiationTo sum it up, in a nutshell:
Heat transfer is not by exchanging heat with air, but by radiation.
Radiation with temperature is called black body radiation.
Wearing clothes will block the heat transfer to a certain extent.
Therefore, there is a conclusion that “you can lose weight by shirtless in winter or usually around 20 ℃”.
So further, how is this calculated?
Stefan-Boltzmann law,Learn about:
The total energy radiated per unit area of a blackbody surface in unit time is proportional to the fourth power of the thermodynamic temperature of the blackbody itself.
Assuming that the exposed area of the human body is 2 square meters, the body temperature is 36.5°C, and the room temperature is 20°C, where σ=5.67×10-8.
Substitute these values into the formula (take the absolute temperature value) to calculate:
After some calculations, it can be concluded that:
After stripping naked, your cooling power is140 J/sec, plus the power of the air circulation, which is approximately150 joules/sec.
So under such heat dissipation power, how many calories are consumed?
The answer after conversion is –
36 calories in 1 second, 21.6 calories in 10 minutes,1 hour about 120 calories.
The principle seems to be no problem.
But there are also fat friends who have raised such questions through their personal experience: “Every day I come home and get naked, but I am getting fatter and fatter”.
Not to mention, this topic has really been discussed once in the physical section of the foreign StackExchange.
Then a netizen directly gave the answer:
Your calculation of human radiated power is correct.
But don’t forget that people also absorb radiation from their surroundings.
Walls, ornaments, etc. in your home may be around 20°C and emit radiation.
In other words, we not only have to calculate the heat released indoors, but also take into account the heat absorbed by the body.
And don’t forget, you may have had a gluttonous feast before you took off your clothes to lose weight:
spicyhot pot, stimulating hot and sour noodles, delicious big burgers, big fries that can’t stop…
Emmm… After all, weight loss in this environment may still belong to“Calorie Deficit”.
But since “undressing” is mentioned, there are also many fat friends who have thought of another thing–sleeping naked:
Why don’t you lose weight by sleeping naked every day?
Can sleeping naked help you lose weight?
Not to mention, scientists have really done research on this topic.
For example, a previous study by the National Institutes of Health showed:
Low temperature (cool environment) can affect a person’s fat and metabolism.
Based on this research, foreign media have stated:Sleeping naked can help you lose weight!
However, before talking about this research, it is necessary to mention a concept that many people may not know but is important for weight loss:brown fat.
Usually, the fat we talk about mainly refers to white fat, which is fat, and its main function is to store calories.
There is actually another form of fat, called brown fat, whose main function is to burn excess calories.
In other words, the more brown fat in the body, the easier it is to lose weight.
The core of this research is to change the amount of brown fat in the human body.
In this study, five healthy men with an average age of 21 years were studied. These men performed regular activities during the day and then returned to their rooms every night for up to 4 months. The room temperature was set at 24 for each month. °C, 19 °C, 24 °C, 27 °C.
The final result of the experiment was that after a month of exposure to mild cold (19°C), the participants had a 42% increase in brown fat mass and a 10% increase in fat metabolism activity. (The red part in the picture below is brown fat)
After returning to normal temperature (24°C), these changes returned to their original levels.
In the last month, which was slightly warmer (27°C), all the changes were completely reversed.
To sum it up, people can gain brown fat by sleeping naked (to keep their bodies cool).
Increased brown fat results in significant changes in metabolic hormones such as leptin (energy expenditure hormone) and adiponectin (regulates glucose and fatty acid breakdown).
In addition, Michael Simmons, a professor of related fields, mentioned:
One gram of brown fat burns 300 times more calories than any other tissue in the body.
As a result, these brown fats will boost your metabolism throughout the day, leading to weight loss.
So, how do we “correctly” sleep naked to lose weight?
Professor Simmons said the temperature when sleeping naked was18℃ to 19℃In between, brown fat turns on only when it feels cold.
However, “sleeping naked helps to lose weight”, there is actually a moresubtle details.
(provided that at least 2 people)
Studies have shown that when sleeping naked with a partner, people are more inclined to do “bed exercise”, which directly leads to an increase in exercise and burning more calories (about 85-150 calories at a time).
Not only that, but direct skin-to-skin contact between people can stimulate the release of oxytocin in the body, which can reduce stress and improve personal mood.
In addition to losing weight, sleeping naked can also reduce stress, lower cortisol, and allow the brain to better clean up toxic proteins.
Hmm, kind of interesting.
One More Thing
Oh yes, today,Tanabata.