The Strelnikova asthma therapy.

Google for "Strelnikova to reduce asthma attacks". A trainer exercises with his very young daughter.

I find the principle of loud nasal inhales very effective. It cured me. The movements of the hands are, I guess, to stop breathing too fast, which might be risky.
1) My asthma was a nuisance but not very serious.
2) I steered clear of sprays to a large extent. The side effects were so threatening and weird.
3) I trained belly breathing..

I find breathing with a stiff upper lip very effective too. It stimulates the heart like a spray ist supposed to do, but naturally.

A wealth of information is on "Strelinikova.freehostia"