(This FAQ/guide will frequently be updated, and changes will be listed up here)
I am making this topic to help new comers or members with some to a lot of experience practice and understand the act of belly inflation.
As a disclaimer: I am not a qualified medical professional. The info provided below is based on personal experience, others feedback, and reference to some medical documents and studies. Should you decide to practice the act of inflation, DO SO AT YOUR OWN RISK! I will not be held liable for any injuries sustained if practiced based on the text below.
First off, to give you an idea based on my personal qualifications, I have practiced belly inflation since I was 15, both orally and anally, and after taking a hiatus for three years at the age of 17, I got back into it and decided to try and research safe practices and proper procedure. Since then I have been trying to help guide others as best as I could towards safe practices as there isn't exactly a hub or guide for this kind of practice. I noticed many posts of new users coming here seeking advice, so rather than have them make a topic, they can ask or post here so all knowledge is in a somewhat centralized location. As stated above this info is based off of experience but does not have a legitament medical basis, so while I have been safe and have followed practices on similar studies (I.E. Enema studies), much of the information is a general guideline and may not apply to all individuals.
So to start: what is belly inflation?
Belly inflation is the practice of inflating ones body parts, either internally or externally with air or water for personal gratification. Many people enjoy it for reasons like (but are not limited to)
1) Internal pressure (notably on sexual organs such as the prostate gland in males)
2) Abdominal distention
3) Restrictiveness after inflation (some users find it harder to move, and are more forced to relax)
4) Cramping (based off pressure)
However, belly inflation doesn't just have to be based off of personally inflating ones body, there is a very large fantasy aspect that spans artwork, video, literature, basically any form of media that you can think of. Belly inflation can also be a common topic in other cultures, such as medical fetishes, the furry fandom, latex fetishists, and so on.
Why do people have this type of fetish: Well, nobody really knows.
The brain is composed of multiple instints that guide us through life to keep us alive. Amongst reproduction, which is one of the strongest of our insticts lies fetishes. These are believed to be in place so that we can find specific traits in parters, even if said fetish doesn't make sense towards survival. Some theories believe this to be a form of mutation, where as perhaps the act of inflation reminds humans of fertility, perhaps as a subliminal desire to become pregnant. Other times fetishes are "planted" when we are young, and grow up to find those fetishes as a sort of coping mechanism to take us to the innocence and protection of childhood without even realising it. Another theory is that inflation itself is an increase in size, and that alone can grant a sense of safety or power over other things (similar to puffer fish inflating and protruding spines, certain animals that try to appear larger than they are, ETC...). Sometimes it's an attraction to things that are soft; the list goes on endlessly. The key thing is that fetishes are generally programmed not by choice, and are usually stuck with humans for life unless the brain changes that by itself.
How to do it.
(The following topic is focused on air. Liquids will follow shortly after)
Well, this is where we go from theory to improvisation. There are two ways to inflate, either orally or anally. A good thing to note is that gas naturally builds up inside of the body, and about a balloons worth of gas is passed every day for each human.
Orally is something everyone has tried at least once, and that's swallowing air. The key thing, however, is to keep the air trapped inside your stomach until it exits the stomach into the small intestine. What you are trying to accomplish is to fill the large intestines and rectum with air. This is generally regarded as perfectly safe (for the average healthy human being) as you cannot create too much pressure; the air would simply stop traveling out the stomach once too much pressure has been reached. Some problems however is that many people are stuck feeling bloated for minutes, sometimes hours and rarely days after delflation as the air is slowly making its way out of the small intestines and sometimes the large intestine. This can cause cramping and restrictive feelings, and sometimes nausea from the internal pressure as well.
Anally many people have tried, and 99% of people (I included) have done it in an improvisonal manner. To safely inflate anally, you would need a medical machine that artifically insufflates your intestines with Carbon Dioxide, and preferably a medical supervisor to monitor you. Most of us don't have access to such equipment, so we improvise with the equipment around us. The most commonly used items are
Bike Pumps
Aquarium Pumps
Their own lungs.
Now, to rank the best overall inflation experiences, I'll start with the best on top making it's way downwards. Please do note that the following devices are not guaranteed to be safe as they can all deliver too much pressure and can cause a rupture.
1) Aquarium pumps. This device is known to slowly deliver air automatically through a tube for aquariums. This device works well as everything is automated, has a long tube, is fairly quiet, and goes at a slow enough place that ruptures wouldn't happen unless you were over-inflated. A problem is if you were to fall unconsious or become dull to the inflation, you could possibly over-inflate and cause damage or possibly death. There has been no recorded cases of death from such a device when used in this manner.
2) Bike pumps. This is a device used to inflate bycicle tires and with an adapter sports balls. By pumping the mechanism, air is shot out through the end into the recipients area. This is generally not as relaxing, but the user can inflate at their own rate and some say that they can inflate a bit more this way. There has been a few documents released (notably in the Phillipines and Thailand) where users have caused internal ruputures from too much pumping, and I've heard rumors that some kids do this frequently as a sort of challenge against others. Of course, these are because people pushed themselves much too far, and done with caution and not over exerting yourself, you shouldn't have any issues.
3) Your own lungs. Actually, this doesnt usually work, because the exhale and trying to blow air into your rectum is cancelled out as the human body clenches too much, preventing air from getting inside. You can however fill your cheeks with air and push on those to get air through the tube, but the same cautions above still apply, and it's usually the hardest to do along with the most tiring.
(More info to follow in a couple days. If there is a specific topic related to oral/anal AIR inflation, please post below or PM me)
A quick note I forgot to mention that is rather important, NEVER TRY VAGINAL INFLATION. I have found a few medical reports on people who have tried vaginal inflation (trying to inflate the vagina and/or uterus) in intercourse sessions. The result is generally an air embolism, which is where air can enter a blood vessel causing a blockage. This can in turn be fatal, considerably if the embolism reaches the heart or the lungs.
Another important note is that air or water should never be introduced into the urinary tract or into the bladder. While there isn't much evidence that I could find, and some people say it's alright, in theory the air could cause air to seep into the kidneys, and can stretch out the muscles along with introducing possible bacteria into the system. Also, I am unsure how the air exits the bladder, and as for water, the chlorine and trace bacteria in it could cause damage and growth in the bladder causing possible infections.
Perhaps air bladder inflation has enough knowledge on it to make fair judgements on the act, however as I cannot find much knowledge on the subject I must assume it is not safe to practice unless you have medical supervision.
(back to the topic at hand)
Since equipment has been established, now we can talk about how to inflate anally. What you want to use with each peice of equipment is some form of lubrication thats approved for use on the human body. Things like personal lubricant would work great. You only want to insert the end of that inflation piece inside your anus about an inch, assuming it is safe to do so (if it's a thin piece of tubing or thin bike pump end, not something large or potentionally sharp). You don't want to insert too far as the piece can damage the walls and you do not want to have a perforated rectum. There are things you can use such as colon tubes, but those are reserved specifically for enema related inflations. I'll get into that more below in the water inflation category.
Once the piece is in, you just slowly inflate away, and keep monitoring yourself. If your a first timer, I can almost guarantee that you will not be able to inflate much as your body has never experienced this before.
You can not push through pain, or force yourself to increase capacity. Doing so can risk a rupture, which can lead to death!
If you feel pain/cramps/uncomfortableness, you need to stop and let your body relax. Most of the time the air has built up in either the rectum or a section of the large intestine, and has to balance and move into the other chamber. You should never force this; the body must do it automatically. Once the cramps pass keep inflating away. You'll eventually reach a point where the cramps are consistant and dont back off, and this is your cue to either retain it a bit, or deflate. Again, DO NOT TRY TO PUSH PAST! You can probably count on not increasing capacity for the first 5-10 times, though I have heard for others it can take much longer. Think of it like going to the gym. You cannot force muscle building, the body needs to first get used to it, rest, and then you can adapt to it. The same thing goes with belly inflation. Your body must adapt to it slowly and on it's terms, and from there you can drastically increase your capacity and distention. After a while, weeks to months, you will notice increased distention, and with luck, patience, and safe practice, you might be able to distend your belly to the point of a 8 month pregnant woman after a while. Some people actually have what's known as a redundant colon, and that is where your colon has an extra "loop" in it. For example, the average human colon/large intestine has three bands that ingested food passes through, to absorb things like water and certain nutrients. Some people develop (generally during their time in the mothers womb) an extra band, sometimes more, so they can end up holding more air/water than the average person with more visible distention.
Initially, you should take a break for a week to play it safe for the first couple times, and then you can probably do it more frequently once the body has gotten used to it. Again, this isnt a race, and your body has to naturally get used to and adapt to it. You have your whole life ahead of you to try this, so you don't want to risk hurting yourself and not ever being able to do it again.
Deflation
One of the small side effects of anal inflation is that for the deflation, it can take an hour or more depending on how much you took in, and can cause bloating along with internal cramps that regulate movement. One thing that some people get during the deflation is a sore anus from so much farting, and that in turn can get very painful to fart. For me, and I don't reccomend it as it can be dangerous, is if you inflate with an aquarium tube or some sort of tube, leave the tube in and keep the end of the tube open. This should be done lying down so you dont risk movement of the tube, and generally when the air hits the rectum, the internal pressure from your body will automatically push it out so you dont have to strain to pass gas. It won't get all of the air out, but it'll get a very substantial amount out (I'd say up to 90% of it if you layed there for a while). Again though, this can be very dangerous because if the tube hits the rectal wall, it can potentially perforate (poke a hole in) it and things like fecal matter can get into the blood, amongst other dangers.
Do not try to squeeze and strain the air out of your body, just pass gas like you'd normally do, and wait for the rectum to fill up with air so you can pass it. Straining can cause higher internal pressure, bigger cramps, and can also cause hemmeroids. It also helps if you massage your abdomen in a clockwise motion to encourage the air to flow out of your intestines.
Also, do not attempt to operate heavy machinery after inflation.
Liquid based inflation
One of the big things about liquid inflation that make it so different from air inflation is the feeling. Many inflationists describe it as "a more heavy, stretchy feeling, that feels more wholesome than air". This is my personal favourite way to inflate anally for a couple of reasons (based off using isotonic water)
1: Less cramping. Compared to air inflation, water inflation is generally less crampy, however, there is much more of a need to "go", as water is much heavier and alerts the rectum that you need to excreete. It's surprisingly common for people to enjoy this feeling,
2: Less bloated after deflation. As air can get trapped in the intestines, so too can air, however, you generally dont feel smaller amounts inside your intestines and you don't feel that slightly painful restriction either. You are altogether more mobile, and some people encourage (usually at smaller safer amounts) moving so that the water can help clean out your insides.
3: Better tools. Since Enema's are a much more common procedure than inflation in general, there is a decent sized market, ranging from basic kits to giant 5 gallon ones (for colonics), inflatable catheders to colon tubes, to recipes and alternative equipments for the experimental group. While many of these products can possibly be used for general anal air based inflation, I do not know enough about safety for these devices, so I can only reccomend the tools mentioned in this part of the section (liquid inflation) for liquid inflation only.
There are of course tons of other reasons and benefits people have, including:
(this will be continuously updated)
How to inflate orally
This is a bit of a tricky topic, because as a general rule it shouldn't be done with regular solutions (tap water, juice, ETC...). The issue is something commonly known as water intoxication. This is where the bloodstream becomes too diluted with water and there becomes a lack of sodium in the body, causing irregular heartbeat, nausea, dizziness, excessive sweating, and in worse scenarios brain swelling and death. There have been a number of related deaths due to this; one notable story was a radio contest where contestants had to drink large quantities of water and not urinate (though you can still die even if you do urinate), where a mother of three died from water intoxication. (Link to story: http://latimesblogs.latimes.com/lanow/2009/10/jury-awards-16-million-in-radio-prank-that-left-sacramentoarea-woman-dead-.html)
So then how the heck can you do it? Well, I do not know of any legitament safe way to do it, so I can't really say. What I can suggest is eating lots of food and then drinking a litre of water, perhaps 1.5 after that, so that the water is absorbed along with salts and other things to keep you fairly in balance. This from what I hear helps with digestion, but don't ever try to force yourself to drink more water than your comfortable with. You'll know when to stop, and you shouldn't try to push that.
For a real life scenario and my own true story, I had tried and experienced slight versions of it before. Back when I was about 15 or so, I had tried to drink a gallon of water in an hour. Most of the times I couldnt, getting just over three litres in, and generally having to use the bathroom and being light headed and sometimes dizzy for a couple hours afterwards. I did try to push through and not only did I end up forcefully vomiting after the amount I had consumed, but I had also ripped my stomach as after the 4th time vomiting or so, the water turned red. I have to say, never have I been as scared of dying in my life. Needless to say, it could have gone much much worse for me, so I was lucky to walk away with just that injury.
Anal liquid inflation
This is a surprisingly common practice even outside the fetish community, and is shared along with a lot of other groups and practices.
(more to follow)
(Not on here too often, replies might be slow.)