Real Housewives of New Jersey star Teresa Giudice has been hitting the prison gym every night and is "getting in the best shape of her life," a source reveals in the new issue of Us Weekly Credit: Manny Carabel/Getty Images

Teresa Giudice is taking the whole "What doesn't kill you makes you stronger" cliche to heart. The imprisoned Real Housewives of New Jersey star has been hitting the exercise room hard while behind bars at the Federal Correctional Institution in Danbury, Conn., a source reveals in the new issue of Us Weekly — and it's paying off.

"She's getting in the best shape of her life," an insider tells Us of the Bravo-lebrity, 42, currently serving a 15-month sentence for fraud. "Every night she hits the gym and has been asking friends to send her workout videos." 

If only they could send her a personal porta-potty, too. "Teresa says the bathrooms are the hardest part of jail because they're filthy and have no privacy," a second source tells Us.

No doubt the mom of Gia, 14, Gabriella, 10, Milania, 9, and Audriana, 5, is looking forward to a long, hot bath once she's released. But that's not the only thing on her "to do" list.

According to the first source, Giudice "writes down everything she wants to do when she gets out." High on her list? A spray tan and a massage.

"She hopes to land the cover of a magazine and get her own cooking show," the insider tells Us of the reality star, who's employed as a laundry worker while in prison.

As previously reported, Giudice received her first visit from husband Joe and their four daughters over the weekend of Jan. 17. They paid a second visit last Saturday, Jan. 24.

For more of the week's hottest stories, pick up the new issue of Us Weekly.