EXCLUSIVE PHOTOS - Britney Spears Puffs Away Her Worries

We know Britney Spears has been working mighty hard in preparation for her upcoming Femme Fatale tour, but we're wondering why the pop star hasn't put aside her nasty smoking habit.

During her recent interview with Entertainment Tonight, Brit admitted to working out hardcore in preparation for her nonstop touring schedule. She told ET's Mark Steines:

"It can be kind of [grueling], especially when you're on stage and you're on your eighth number. You get really winded and you're like, 'How can I do the rest of the show?'..."

The smoking habit probably isn't helping her whole winded situation. Let's hope our girl will extinguish her nicotine fix asap.

See more of Britney's recent interview ... after the jump.