Inside Jessica Simpson's Quarantine Diet and Workout Regimen (Exclusive)

The 39-year-old fashion designer showed off her progress in a new Instagram snap.

Jessica Simpson is staying committed to her workout routine and diet even while in quarantine with her three kids -- and ET is sharing how she does it! 

The 39-year-old fashion designer showed off her progress on Wednesday in a sexy post-workout snap on Instagram. "Woke up before all three kiddos to get my steps in and spend time with me, myself, and I. Move move move for your own mental health," Simpson captioned the mirror selfie wearing her own workout line

So how is the famous mama staying in shape on lock-down?

A source close to Jessica tells ET, "She is walking outdoors and on her treadmill. It’s the way she stays sane, so it’s as much for mental health as it is for physical wellness."

In terms of diet, it's all about moderation for Simpson. "There has definitely been a lot of baking going on with the kids and she doesn’t totally deny herself," the source adds, noting that portion control is important for the mother of three. 

As for her husband, Eric Johnson, and their children, Maxwell, 8, Ace, 6, and Birdie, 1, the source tells ET that the family is doing great within quarantine. 

The source adds that they have the same challenges as all families do right now with homeschooling and frustration over not being able to see friends or play sports. However, they are making the best of it and using the extra family time together, just the five of them. 

Prior to quarantine, ET sat down with Simpson to chat about her new memoir, Open Book, and the love she has for her husband. Check out the exclusive interview!

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