What fat are you talking about? Today I’m talking about the fat on your body as opposed to the fats you eat. Did you know there are several types of fat stored on your body? Firstly let’s take a look at ‘white’ fat. This is the majority of fat stored on your body and when your trainer talks about burning fat, they are most likely talking about this. It’s one of the two fats that come under the heading of ‘adipose tissue’ and is the main energy storage holding the triglycerides that we burn for energy.
The other adipose tissue is brown fat, which not too many people know about. It’s found in much smaller amounts (only several ounces) and only until recently was thought to be fairly useless. Recent research has found that when stimulated, brown fat can actually burn calories. Brown fat is found more in newborn babies and it is believed that it creates heat where their muscles are not developed enough, like ours, to shiver and produce heat this way.
Next is visceral fat. This is fat found deep in the core and is thought of as a more dangerous form of fat, in large amounts, as it surrounds the organs. The good news with this is that it has a good blood supply and as such can be dealt with easier.
The last one I want to talk about is subcutaneous fat, this is the fat that’s held just under the skin and measured by body fat callipers. Where this is not as dangerous as other fats, it’s the kind of fat that sticks around and hard to get rid of. Women tend to store more of this (and white fat) around the thighs, hips and waist (due to oestrogen), where men hold more around their middle (due to testosterone – funny how hormones keep popping up). Luckily for women fat in these places is seen as less of a health risk as it is stored away from vital organs.
So that’s the fats covered, how do I lose it?
There are three things we need to do to lose fat. We need to –
Release fat from storage
Transport it to the muscles
Burn the fat in the muscles
At any stage things can go wrong, but let’s look at how it should work, followed by what can happen.
The body will send a message for fat to be released; I normally relate this to people’s cholesterol as people have a bit more knowledge of how this works.
Very basically there are two types of cholesterol, LDL and HDL. LDL is seen as bad and HDL seen as good. LDL clogs up the arteries and HDL breaks this down. Now it’s not so much a problem if LDL levels are high if you have high HDL levels to combat it. The problem comes when there is a large difference in levels.
This is very similar to fat storage/release. LPL (Lipoprotein Lipase) tells the fat cells to store fat and HSL (Hormone Sensitive Lipase) tells the far cells to release the fat (Triglycerides).
Transporting the triglycerides to the muscle –Once released from the fat cells the triglycerides enter the blood stream and are transported around the body to the muscles. It’s good to note here that it’s not the fat around the muscle that is necessarily used – many people think doing sit-ups will lose the fat on their belly’s, and yes some fat may be released from fat stored there, but it’s more likely that the fat cells with a better blood supply will release the ‘fat,’ meaning that the body chooses where you will slim first, not you.
Lastly the ‘fat’ needs to be used by the muscle. Within the muscles we have mitochondria which are the power plants converting triglycerides into ATP, Adenosine Triphosphate, which is the body’s currency – all cells can use ATP as energy including the muscles.
So where can this go wrong?
Firstly the ‘message’ sent to the fat cells needs to be primarily HSL. Notice this is “Hormone” sensitive lipase and not ‘calorie’ sensitive lipase. The food we eat affects hunger hormones and depending on the type of food we eat depends if we get more LPL or HSL. Other things like exercise will help raise HSL.
The only problem with transportation is making sure we have a good blood supply to the fat. Some people go to the gym get on the treadmill and stay there with a fan blowing on them or pick the treadmill under the air con. The fan blows cold air and will close the veins and arteries. When the body is warm the blood vessels open up allowing better blood flow to them hard to reach places.
Now just because it’s been released and taken to the muscle does not guarantee it will be used, it can just as easily be transported back and stored as fat again. If we look at how a body builder builds muscle, we want to do the opposite. It’s very hard to build muscle and burn fat at the same time, the body doesn’t like to do it. A body builder will have a workout and immediately have a protein shake/bar which gets broken down into the blood stream and used to repair and build muscle. If we are after fat loss we don’t want to use the protein, we want to get rid of the ‘fat’ in our blood before it gets stored again. Having a training session like HIIT (high intensity interval training) is a great way to increase HSL and release fat. After the session we don’t want to eat straight away, a casual walk for 30 minutes will burn up any remaining ‘fat’ in the blood.