Shannen Doherty might not be feeling 100 percent, but she's still sticking to her fitness goals.

Just one day after undergoing chemotherapy treatment, the 45-year-old actress was up and dancing. "Let me tell ya, shaking your booty is hard work with my Neda who's been helping me move and get toxins out," Doherty captioned an Instagram video of herself dancing in her workout gear. "Yes I was tired, yes I wanted to be in bed but I went and moved and felt way better. Any exercise during illness is good. We can do it!!!"

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After exercising, Doherty shared a relaxing selfie where she posed with her mother. "And sometimes you just want to collapse on the couch and watch TV with your mom," she wrote. "I love you mom. @themamarosa #fightlikeagirl"

Doherty has been diligent about documenting her battle with breast cancer, and her former co-stars and peers have commended her courage. Alyssa Milano, who starred in Charmed with Doherty, recently told ET that she's reconnected with her former co-star.

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"I've reached out to her, yes, and I try to continue to reach out to her once a week," she shared with ET on Tuesday. "I tweeted, I [direct messaged] her and I obviously told her my concern and how everyone was on her side, and we're all supporting her, and she was very appreciative that I reached out, which was very sweet."

"It's such a horrible, horrible, horrible, horrible illness, so to see anyone struggle like that in such a public way is heartwarming and gut-wrenching all at the same time," Milano added.

Check out more of her interview: