The 46-year-old flaunted her ripped physique and toned arms during the event while wearing a tiny glittery purple bikini and clear stiletto heels.
“She wanted a new challenge and pushed herself to the extreme,” a close friend told People. “Right now she is in the best shape of her life.
“She has lost a bunch of weight,” the source continued, adding that the reality star is “even more fit than when she got home [from prison].”
In 2015 Giudice was released from prison after serving 11 months for mail, wire, and bankruptcy fraud.
The reality star, who entered the 40-plus division, finished in third place.
Her brother, Joe Gorga, was there to support her, as was her trainer, Tara Zito.
Meanwhile, husband Joe Guidice is currently serving his 41-month sentence for fraud and is said also to be jumping on the fitness bandwagon.
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