That's in contrast to the 26 percent of adults who don't have a disability and get no exercise, she added.
Carroll noted that government guidelines for Americans recommend that all adults, including those with disabilities, get at least 150 minutes -- 2.5 hours -- of moderate aerobic physical activity each week.
If some people with disabilities can't reach this goal, they should do the best they can. The key is to avoid inactivity, Carroll said. "Some activity is better than none," she said.
People should start slowly, and exercise for at least 10 minutes each time. They should gradually increase their activity to reach the goal of at least 2.5 hours a week of moderate exercise, Carroll said.
Activities can include walking, swimming and biking. Even rolling yourself in a wheelchair is exercise, she said.
People with disabilities can encounter barriers that deter them from exercising. These include physical barriers such as no curb-cuts on sidewalks, no ramps into gyms, and parks and trails that aren't safe or easy to navigate, Carroll said.
She also said psychological barriers play a role. These include lack of support from family and friends or feeling self-conscious about using a gym and asking for help.
People with disabilities need to develop the confidence and the belief in their ability to do aerobic exercise as a way of improving their health, Arias said.
Samantha Heller, a senior clinical nutritionist and exercise physiologist at NYU Langone Medical Center in New York City, said, "For some people with disabilities, the idea of movement and exercise is daunting and they do not know how or where to begin."
Health professionals can take a proactive approach with their patients with disabilities by referring them for physical or occupational therapy, she said.
"Physical and occupational therapy are terrific places for people with disabilities to kick-start their exercise programs. Patients, too, can be proactive in their own health care and demand referrals for physical or occupational therapy," Heller said.