What was Rihanna doing while much of the world slept?  Working out her dance moves. The singer has posted a video from a 12 a.m. dance rehearsal that showed RiRi putting her finishing touches on the choreography to her song "Pour It Up," in anticipation for her Diamonds World tour. 

As "Pour It Up" plays in the background -- all about drinking Patron and throwing up dollars at strip clubs -- Rihanna looks low-key as she dances and pretends to hold a mic during the midnight session .   While the choreographer explains Rihanna's vibe and hip-swiveling moves as giving off the energy or "feeling of, like, a stripper slash hood," one commentator says Rihanna looks "bored as hell."

The singer's Rihanna for River Island clothing line debuted during London's fashion week, but her rehearsal fashions were all about working out. In the video, Rihanna wears a black graphic-print sweatshirt and sweatpants with a backwards baseball cap and, later, a pink and grey workout outfit and knit cap as she goes through the motions with her dancers.

Rihanna kicks off her Diamonds World tour in support of her album Unapologetic on March 8 in Buffalo, New York before heading across the U.S. and Canada and onto Europe.  The tour wraps on July 28 in Finland .

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