(CNN) -- Fans of "Dancing With the Stars" know how grueling the competition can be.
Contestants practice for hours a day, and almost every season some celebs are brought low by injury. So how in the world will Valerie Harper, who just months ago announced that she had a terminal form of cancer, go for that mirror ball trophy?
Apparently with the same spirit that caused the "Rhoda" actress to offer this up for fans:
"I hope you dance! I hope you dance," Harper told CNN on Wednesday. " And that's what I'm saying to everybody, that's just my message. Dance."
Harper announced in March that she had been diagnosed with leptomeningeal carcinomatosis, a condition in which cancer cells spread into the membranes that surround the brain and spinal cord. But Harper told CNN that she does not have brain cancer.
"I have lung cancer," she said. "It is situated in the lining of the brain; it's not even in the brain."
Her husband, Tony Cacciotti, encouraged her to sign on with the hit ABC dance competition, she said. He runs the couple's production company and had been considering her participation for a few years.
The actress said she initially resisted the idea.
"I said, 'Give me one good reason,' " Harper recalled. "He said, 'You have cancer! Get up there, and show people that you can dance and do -- and the doctors said it's fine to exercise. Encourage people to move, to exercise, to do all the things that will be good for them, and mainly not to sit in the house and glower and worry and feel sorry for yourself because you have this disease and anything else.'"
Exercise is generally encouraged for patients, according to the American Cancer Society.
"At one time, patients with cancer, especially in the advanced stages, were often told by their doctor to rest and limit their exercise," the organization's website says. "But newer research has shown that exercise is not only safe and possible during cancer treatment, but that it also can reduce symptoms and improve quality of life."
Harper, 74, said she has been responding well to treatment, though she disputed reports she is in remission. Thinking about death makes everyone fearful, she said, "and we gloss it over; we pretend it's not happening, that it's over there."
"This death sentence made me look it in the eye, and then once you do it, it's a great freedom," she said.
The show's host, Tom Bergeron, said Harper is in great spirits, even joking with him that "Hey, I'm past my expiration date!"
"I think arguably we have some of the (most) poignant story lines of all this season, particularly with Valerie," he said.
Harper's dance partner for the show, Tristan MacManus, said the actress' participation goes beyond her being ill.
"It's not about someone who's sick doing something," he said. "I think it's just about someone who's willing to do something."
CNN's Jacque Wilson contributed to this story