Ich vermute, es ist das Austreten der Luft, und eine Menge Stehplätze in Fuß, das Blut ist nicht immer auf alle Teile des Körpers. Aber es muss die Luft. Ich bin in einer Chors und niemand jemals ohnmächtig:))

There are several reasons a singer might faint during a performance. I was in a concert once where several people, including myself, fainted during the final song. It was a surprise for me because I’d never fainted before. The concert was really long and there were a lot of hot lights shining on us. I made the mistake of wearing heals which caused my legs to ache after standing in the same place for a long time. I also ate a late breakfast so I didn’t have any lunch. Since it was a 2:00 concert I didn’t have enough nutrition to sustain myself. The same was true with water.

In my experience I have found that it is usually a combination of things that cause a person to faint during a concert. More often than not the temperature on the stage, lack of water, and the length of the concert are the major factors.