Pop star Britney Spears, who is on a world tour called
, is struggling with her energetic dance routines as the high-voltage performance makes her dizzy and nauseous. It also costs her clumps of her hair.
In one of her most recent shows in North America, a suspended dancer yanks off a handful of hair from Spears' head as he attempts to pull her into the air with him, reported contactmusic.com.
"The choreography is insane. It's so fast it is really taking its toll on her (Britney). There is one move during (the song) Touch Of My Hand, where two guys dangle from the ceiling and pick her up upside down, which is really getting to her," said a source.
"She spins around for nearly five minutes some nights. The blood rushes to her head and when she gets down she complains of nausea and dizziness. There have been a couple of times when she ran off stage and vomited," added the source.