DALLAS - In the past, patients diagnosed with chronic or life-threatening disease were told to conserve energy, rest and reduce physical activity. Now, science shows people should do the exact opposite.

"A lot of them coming off the cancer, they don't have too good of a balance or it's like they're not strong," said Roosevelt Brown, a patient facilitator with the Fit Steps for Life program.

Fit Steps for Life is an exercise program tailored to people with cancer.

"When I first came, I couldn't even lift my arm this high, but now I'm good," said Johnnie Williams, a breast cancer patient.

Williams said she has always known physical activity is good for the body, but she didn't realize how good.

Studies prove exercise for cancer patients can do so much more than just improve their mental and physical strength.

"Multiple studies that have shown that cancer patients who actually work out tend to tolerate their chemotherapy better," said Dr. CK Wang, an oncologist at the Cancer Institute of Dallas. "And, also working out may also decrease their risk of the cancer coming back."

A National Institutes of Health study shows vigorous activity at least three times a week can reduce the risk of breast cancer by 30 percent.

It's one reason why the Cancer Institute of Dallas has built a gym that offers free trainers for any patient diagnosed with any type of cancer.

Rick Hutchings recently stepped on the treadmill for the first time after learning he has colon and kidney cancer 18 months ago.

The results, he said, have been "phenomenal mentally, cognitive function, balance and agility, self-esteem comes back, less fatigue [and] better strength."

While Williams said breast surgery, radiation and chemotherapy is hard on top of the exercising, she is convinced her regular workouts will be worth the strain.

"[It] just brings tears to my eyes," she said, "But, I'm good."

E-mail jstjames@wfaa.com