Getting "high" by breathing air

[Crayon Boy]

Some of my m8s have been doing this lately and they have uploaded few vids on youtube.

Basically what you do is sit down and start breathing fast and deep for like 2 mins, then u stand up fast and stop breathing by urself or another person stops you from breathing with a scarf lets say.

Well, they say it feels like ur high first, then u pass out for few secs (although the passed out person feels like he's slept much longer) and after a few tries ur brain and lungs start hurting...

Vid:

http://www.youtube.com/watch?v=CFCd7_PeKAw



Ive never tried this and i doubt i ever will. I bet it does huge damage to ur brain.

I didnt tape the vid.