London: Former Pussycat Dolls` singer Nicole Scherzinger says working with rapper will.I.Am on his upcoming album `Willpower` was exhausting.
The 34-year-old said the Black Eyed Peas member is always "always thinking and creating", reported The Daily Star.
"He`s like a crazy ball of energy that just bounces off the walls. He`s always thinking and creating," she said.
The `X Factor` judge also said that she has worked with will.I.Am on her own solo project.
"He executively produced pretty much everything I`ve done, up until now," Scherzinger said.