From a message I sent to the CFS-20s mailing list in May, 1997. The quoted parts are Roger's and have been used with permission.
Please note that I am NOT a biochemist or a doctor or anybody else who's qualified about this stuff! What's written below is my understanding from what doctors and biochemists have told me. If there are any mistakes in it, please let me know via email and I'll fix it up.
Just for clarification, this is what's supposed to happen:
> When you exercise any muscle it needs energy. Energy comes from > carbohydrates which are broken down and stored as glycogen in the > muscle cells. For the muscle to get energy from the glycogen it > must be combined with oxygen (from the red blood cells) and enzymes > (from the muscle cell itself). This whole process is known as > aeorbic metabolism.
This is what seems to happen in (some?) CFS patients:
> However, when there is a lack of oxygen, the result is anaerobic > metabolism, in which an excess amount of lactic acid is produced. > This is similar to what happens in a marathon runner. In a healthy > person this lactic acid would be burnt off after a day or two, but > in someone with M.E./CFS/CFIDS, the build up is much quicker (after > relatively little exercise), the muscles accumulate this excess > lactic acid and it takes a lot longer to get rid of it. This is > what leads to pain, tenderness, fatigue (and sometimes twitching) in > the muscles being almost perminaent even after very little > exercise.
This anerobic metabolism is also called 'catabolism'. It's basically what happens when your muscles start breaking themselves down to get the amino acids back to use them for energy. It's generally a Bad Thing, healthwise, and only generally found in three classes of people:
- Endurance athletes, like marathon runner or long-distance swimmers, after they have just run a marathon or something. In this case it happens because all the usual available energy sources have been used up, but energy is still required.
- People with severe cases of anorexia or extreme malnutrition like you'd see in some third-world countries. Here, it happens because no new energy (ie food) is being put into the system and so the energy has to come from somewhere else, and the only place left is muscle tissue. If this is happening, then the person is probably sick enough to be put in hospital ASAP.
- People with CFS. Nobody really knows why - for some reason our muscles *think* there is no available energy when really there is, or there's some other problem that means they can't use the available energy.
This is NOT just a theory. One of the major things that the Newcastle urine tests find is evidence of chemicals in the urine that can only be put there if catabolism is happening.
So basically, even mild exercise (slow walking, getting up to go to the bathroom, whatever) in somebody with CFS makes the body react as if it's been running a marathon!
Extra Note: This doesn't mean that you should do no exercise. The catabolism is (this is my understanding, anyway) is part of what makes us crash after exercise - so if you can find exercise that doesn't make you crash, then it's a Very Good Thing and stick to it. But don't be surprised if that amount is a lot less than you expect.And don't fall into the physiotherapist's common trap of "if you start small you'll be able to increase it". This works for healthy people because when they start doing exercise their fitness incrases and their body gets more efficient and transporting energy (glycogen?) to the muscles. But our problem is NOT lack of that energy, the problem is that isn't not being used properly, so if your CFS isn't getting better, then that place where the catabolism starts to kick in probably won't move, so you probably won't be able to increase how much you're doing. And that's okay - it's just CFS.
