Sydney underwent a major transformation for her role in Christy, the biopic following the life of former professional boxer Christy Martin. For the part, the actress had to work out for hours on end and went on to gain 30 lbs.

“I came on board to play Christy, and I had about three and a half months of training,” she told W magazine. “I started eating. I weight-trained in the morning for an hour, kickboxed midday for about two hours, and then weight-trained again at night for an hour.”

She also donned a brunette wig for the role, looking so different from her usual bombshell persona. Sydney then had to quickly shed the weight to prepare for her role in The Housemaid, and told People that she was “really strict” about her health.

“When I was training, it was really hard to put on all the weight. I was eating so much food. Like, everything you could possibly imagine,” she told the outlet. “And then I was downing protein shake after protein shake and taking a lot of creatine, which just makes you bloat.”

“When you stop working out and taking all your protein shakes, you lose muscle super-fast,” she added. “It’s the first thing to go before fat. So, that, I dropped within two weeks.”