This is called micro-handstand. According to the description in "Fitness of Human Inverted" written by Mr. Guan Feng, micro-inverted can treat and alleviate many diseases. Mr Guan Feng has many successful cases.

There is also a kind of inverted bed, sleeping from head to toe, which is also based on this principle.

So is the inversion.

Of course, the same is true of practicing handstand.