Shannen Doherty is one tough cookie!
The former Beverly Hills, 90210 star, who is currently undergoing radiation treatment for breast cancer, took to Instagram on Wednesday to prove to her fans that nothing is preventing her from staying positive or, in this case, busting out her best dance moves.
WATCH: Shannen Doherty Breaks Down Over Cancer Battle: 'I Don't Look Past Today'
In the adorable video, Doherty rocks a comfy pair of gray sweatpants and a simple black T-shirt while performing an aerobics exercise to Pitbull's "Fuego" alongside celebrity fitness trainer Neda.
"Radiation is tiring. It builds up within you and sometimes one just struggles to keep their eyes open," Doherty, 45, captioned the video. "You can see how tired I am here but I'm still moving!! Any movement is so good during treatment, not just for the body, but for your mind as well. #cancerslayer."
A few hours after the video was posted, Doherty revealed via Twitter that she would be doubling up her radiation treatments in order to speed up the process.
"Meanwhile..... gonna do a double up day of radiation so I get completely finished this week!!" she shared.
WATCH: Shannen Doherty Shares Cancer Update, Reveals She Feels 'Blessed'
And when a fan asked, "What's next after radiation?" Doherty was quick to respond.
"@Carlychristina8 wait for radiation to leave body, get tested and hope we got it all," she explained. "After that, I start the road to reconstruction."
Doherty, who was diagnosed with breast cancer in February 2015, exclusively revealed to ET over the summer that her cancer had spread. "From one of my surgeries, we discovered that some of the cancer cells might have actually gone out of the lymph nodes," she said at the time. "So for that reason, we are doing chemo, and then after chemo, I'll do radiation."
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Since then, she's been very open about her battle with the illness, often sharing personal and intimate videos with her followers and documenting her journey to recovery.
Despite her difficult battle with the disease, she's remained positive. When ET caught up with Doherty on the red carpet at Stand Up to Cancer's telecast last September, she said she felt "blessed."
"Cancer has, in a strange way, done some amazing things for me," she explained. "It's allowed me to be more me, like much more in touch with who I am, and much more vulnerable and the person that I always was, but I think it got hidden behind a lot of other stuff. My marriage [with Kurt Iswarienko] was always fantastic, but it's even better now."
"I stand here to support every single person who has cancer, and I stand here to also support the husbands and the family that has to go through it," she continued. "Because it's not just the people who have cancer. It's the families too that go through it that it's very hard on."
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