The Jersey Shore star was released from prison earlier this month after completing his eight-month sentence for tax evasion, and spent some of that time working on his physique. Sorrentino said on Instagram Friday that he lost 36 lbs.
“This is what it looks like when you turn a negative Situation into a positive Situation,” he wrote. “#clapbackseason lost 36 lbs.”
“I went to sleep every night at 10 p.m. I woke up every morning at 7 a.m. and did fasted cardio for about an hour,” he said. “I was practicing intermittent fasting while I was in prison. My window of intermittent fasting was between 16 and 17 hours on the weekdays, and 18 and 19 hours on the weekends.”
Sorrentino said that along with intermittent fasting, he was working out “two to three times a day,” and would work out more on holidays to deal with the pain of being away from his family and friends.
“Because, you know, on your birthday, or Easter or something, you’re in your feels a little bit,” he said. “You’re like, ‘You know what? Today I’m gonna do something to make my future self proud.’ And I put in my three [workouts].”
He also had a bit of weight to lose after overindulging in fast food before leaving for prison.
“I gained a couple of pounds, but I had the time once I was in prison to concentrate on being my best self and losing the weight,” he said.
Sorrentino said that focusing on his diet and exercises made his prison stay easier.
“I had to continually challenge myself, whether it was in the gym, and/or diet,” he said. “I was reading books, the Bible and trying to progress spiritually as well. Because if you do not keep yourself busy in there … I saw a lot of guys that weren’t doing those things and you saw depression and anxiety take control … I felt very accomplished staying busy in prison.”
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“Before he went to prison, he was eating everything in sight,” Guadagnino told PEOPLE. “But he knew the principles of it and now he’s really applying it.”