copy from an older post, after my visit at my doctor: "Our whole body gets into a "defense" state and we are tensing our muscles a bit, not to feel from outside. Our muscles will start to twitch and we will feel vibrations never felt before. I never knew it before, but he said most people with "it" breathe way to fast , so we have way too little carbon dioxide in us.Called Hyperventilation. This gives our muscles the creeps, they get into a "twitchy" state. I was kind of sceptic, I never thought that I breathed to much. Now they measured my CO2 level and I was stunned: normal level of CO2 should be around 40mmhg...mine was..21,5 mmhg!!! Fasciculations are a very typical side effect of chronic hyperventilation. Together with parestesias and muscular pain(ex intolerance). And now the vicous circle starts....those symptoms make you stress, stress even lowers your nerve filters, symptoms get worse, you increase you breathing, CO2 drops, fasciculations through the roof, muscular pain, exercise intolerance as muscles don't work right under these conditions.Then they made me hyperventilate even in a "safe" surrounding......extreme hyperventilation and I had an explosion of twitching, pins and needles, pain and dizziness in my body, it was like fireworks going on....then they gave me CO2 (re breathing)and it calmed down. I was really impressed. They said it is possible to calm all that down if you are able to meditate with good breath control, but as soo you come out of your meditation breathing pattern you will fall back to wrong breathing immediately and your back to step 1.Now I can tell U: I still have BFS to some extend. Relapses with infections, stress etc. But while in meditation, when I am concentrated on my beathing and can REALLY calm it down....I can make all my twitching and vibrating go down to zero. No matter from what level I am coming, zero, nada. Just by breathing control. But I still have NOT learned how to completely stay at that level. And the mean thing is, that for "us" our brain thinks that this s completely normal and will always try to reach the 25% ior whatever, so we must ACTIVELY try to work on ot sensors to get them back to a setting, where they want to reach the 40mmhg. That is tough, I am working on it every day since last february!!another quote from a paper about "spasmophilia":The General Adaptation Syndrome is also thebasis for spasmophilia. With this syndrome, theneuromuscular over-excitability of the stripedand smooth muscles plays a central role. It can besaid that hyperventilation is a part of thissyndrome. The hyperventilation phenomenon isnot something on its own, but is part of a largerpicture. Other symptoms include tiredness,stiffness and twinges, muscle cramps, stomachand intestine complaints and allergies. Apsychosomatic component is very usual. Thesesymptoms seem to be quite general, but they canbe specified. Dr. Van der Vlies in Amsterdamintroduced spasmophilia in the Netherlands bywriting an excellent review in the JournalOrthomolecular (nr.l, 1988). Patients with spasmophilia are difficult"starters" in the morning, and in the evening theyare overactive. In their hands and feet they feelneedle and pin pricks (like the complaints afterpinching off arterial circulation). Ticks (eyelids)and tiny muscle twitches are typical symptoms.The extremities feel heavy and stiff. Crampsshow up when at rest and ameliorate duringexercise. Also there may be cramps in the bellyand back musculature, which initiate back andneck pain. In many cases these symptoms areconnected with psychological factors.The lack of CO2 means, that the blood buffer system cannot work correctly. A change in blood acitity though, not only affects the exciteability of muscles and nerves per se, but also minimizes the availability of calcium and mg to nerves/muscles which causes an additional hyperexciteability around the synaptic end plate.oh, and see here:
OK, this is from 1953 so it is only describing it not bringing up EMG results but...muscular spasms, myalgia, tremors, twitching movements...numbness, tingling, skipped heart beats...sounds a BIT like us, doesn't it?
I think some contents of this site above are just well a bit OVERINTERPRETING all of it, but basically this is also what my doctor said and teaches and what helped me...without paying for it. The device I used for re-breathing was a bit similar to the ones there. If someone wants to find out, I guess it might be worth a try.
...actually... 
Caue that means, in this regard I'm healthy!!!Still, would have loved to get rid of the twitching with breathing exercises....
. but no strange twitching. I tried on my mum and my sis , undercover of course, pretending to be applying one new spectacular face cream...no twitching. At some point, where I started to accept all of this, I also accepted it, but I am reminded daily when applying my make up. I just blamed it on BFS. Now it has a name