Hypnic jerks are common and normal - they occur just as transitioning to sleep. I get them at times, especially after a stressful day. For me it gives an odd feeling for a few moments after, which I now associate with a sensation of relaxation. It usually then means I am going to sleep better than u...

An Aussie here. There is a viable setup in my area that covers what I think French Nurse is asking A Nurse (who has sleep apnoea) runs an Air Liquide Healthcare CPAP shop. It is integrated with a chain (Snore Australia) that offers at-home or in-hospital sleep studies. The demographic of the area is...

Vitamin D at 22 might not improve with a routine daily supplement - that tends to just maintain the level. A loading dose of say 4 Vit D tabs a day for a month or so can do the trick at least as boosting levels to normal is concerned.

75% for a few seconds might be an artefact from a loose probe or laying on your arm - was the rest of the night not too bad? 83% saturation at 9k feet may not be too bad either - air is starting to get a bit thin up there. Like you I keep very active, but have low 90's awake saturation at rest while...