Designer: Beyonce Was 'Losing Weight Every Day'

Designer: Beyonce Was 'Losing Weight Every Day'

One of the most anticipated events at yesterday's Super Bowl was Beyonce's performance during the halftime show and ET spoke exclusively to the superstar's costume designer about her her rigorous rehearsals and how much work went into her outfits.

"When a performer is working so vigorously, they're shrinking constantly, and so she was losing weight every day," fashion designer Rubin Singer told ET. "So we had to keep taking it in and taking it in and taking it in and doing tweaks and changes."

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Singer said he was based in New Orleans all last week preparing for Beyonce's Super Bowl performance and that a team of 14 people put about 200 man hours into producing and tweaking the costumes. "When you have the dress rehearsals and you actually get to see the footage the next day, or that night, and you see all the little nuances that you need to change," he said. 

In addition to Beyonce's costumes, Singer also created the outfits for former Destiny's Child band member Michelle Williams as well as the jackets for the show's 120 backup dancers.

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