Is this stupid, or really something?

Brown fat, metabolically active fat.

It's supposed to only be used to burn calories and warm the body (not through insulation, but the heat given off as if burns calories). It's been proven to be present in children and babies (aka, baby fat), but scientists are discovering it's on adults too. Apparently something as small as the amount as 80-100 grams can burn 500 calories, and most of this fat is located around the upper portion of the body (cervical/axillary/sternum area).

Here's my theory:

-Swimmer and cold weather athletes have more brown fat that others. The cold temperature forces the body to warm itself up, hence through the activity of the brown fat. 

-Hypermetabolism in recovering anorexics is partly due to brown fat being "triggered". I do believe that an anorexic needs significantly more calories to repair damage (more than just gaining fat, actually fixing the body), but in some cases where they are on 4500+ calories AND bedrest, I think that brown fat could be triggered. 

What do you think? 

if swimmers had a greater amounts of  brown fat - you are arguing they are more metabolically active than those with less amounts of brown fat cells? but swimmers are actually the least lean and struggle the most with their weight in all categories of competitive athletes. yes michael phelps is an exception.

the greatest problem with anorexia and hypermetabolism is that much of the damage lies inside the body. there are huge quantities of muscle wastage. mitochondria are numerous in myocells. the muscle waste occurs not just from the skeletal muscle - enhanced by exercise, but from essential muscle. cardiac muscle and smooth muscle. these muscle fibres are as metabolically active as skeletal muscle. so while the body receives extra calories, much of the calories go into the reformation of this wasted muscle. in creating new muscle, it is forcing new calorific demand. this is also why hypermetabolism stops. because everyone has an individual genetic muscle composition. much like a unique fat profile. when the correct muscle composition has been restored the extra calories are stored as energy - glycogen in the liver, glycogen in skeletal muscle and eventually when both these stores are full - body fat

Okay, I get the recovering anorexic part.

But as for swimming, I've found swimmers eat significantly more than runners. The cold temperature of the pool creates the need for them to keep warm- thus more brown fat and more hunger. This hunger in turn, makes them eat more, sometimes exceeding the extra burned from brown fat (because after a three hour practice, you just NEED food, and don't think about it too much!) and thus be heavier. 

I think this is a job for science. Like with research and experiments and supported data. Supported data is a good thing.

Fat is just a deposit it doesn't burn anything and swimmers do not work out in ice cold water because an efficient swimming routine means that you come out for air every stroke or every 2 strokes so the head is submerged most of the time, it's impossible to keep your head down in cold water, you feel like you can't breathe properly, your ears start to hurt and then you just have to get out of there.

Also swimming is hard work, it burns a big amount of cals and develops the big core muscles, it's normal to empty the fridge after a serious workout and to be heavy thanks to the bulky muscle mass.

Cold weather athletes are dressed properly, with layered clothing, nobody wants to risk pneumonia by being sweaty in the cold wind.

I've read many articles that say fat does this and fat does that but it's all nonsense, fat is storage for "rainy days", it does nothing to burn energy.