I think Logic is right. Once I was asked about this and couldn't come up with better idea than various muscle groups relax not exactly the same time and the difference between their tension trigger a spinal reflex.
There are flexor muscles and extensors to move the same articulation. If, for example, the flexor muscle(s) remain highly tensed but tension of the extensor(s) decrease above a given level a reflex movement is triggered.
It should be similar to the situation when Major Tom and I come on over to you and while Tom hold you down ruthlessly I start to beat your knee with a giant rubber hammer until you kick forward lol.
Maybe you should relax before sleep / projection or if you already do that then you need do it in an another way to prevent all this to happen.
There are flexor muscles and extensors to move the same articulation. If, for example, the flexor muscle(s) remain highly tensed but tension of the extensor(s) decrease above a given level a reflex movement is triggered.
It should be similar to the situation when Major Tom and I come on over to you and while Tom hold you down ruthlessly I start to beat your knee with a giant rubber hammer until you kick forward lol.
Maybe you should relax before sleep / projection or if you already do that then you need do it in an another way to prevent all this to happen.