Marcela Turnage does the challenging, such as skiing, sailing and horseback riding. And the more mundane, like shoveling snow from the driveway.
What the active 32-year-old mother doesn't do is walk. She hasn't since a car accident in 2002 took her boyfriend's life, as well as one of her legs, and left her paralyzed from the waist down.
That's why standing and "looking people in the eyes" may be among her most satisfying physical achievements yet. She began doing slow laps on her feet this fall during physical therapy with the aid of a new "exoskeleton" called ReWalk.
"After the first time, I was so happy that I cried driving to work afterward," she said. "Just to stand and walk for an hour or two or three a week, it's awesome."
Therapists at the University of Maryland Rehabilitation & Orthopaedic Institute followed development of exoskeletons for years before unveiling them to five patients this summer. ReWalk is one of at least seven robotic exoskeletons in use or in the works around the globe. Three are approved for therapy in U.S. facilities.
Turnage came to the institute recently for her 20th session with Jean McQuaid, a physical therapist, and Jerry Morgan, a physical therapy assistant. They helped her into her metal suit and then spotted her as she stood and walked with crutches for balance.
She started the exoskeleton with the push of a button on her wrist. Another button told the battery-powered machine to begin moving. From there, sensors detected subtle changes in Turnage's center of gravity, such as when she leaned forward, to mimic her gait.
ReWalk was approved for use in U.S. hospitals in 2011 and is now used in 14 hospitals across the country. It was the brainchild of Dr. Amit Goffer, a quadriplegic who founded Argo Medical Technologies in Israel in 2001 but now lives in Germany.
The home version has been used in Europe since 2012, and company officials said U.S. Food and Drug Administration approval here could come as early as April. FDA officials did not respond to request for comment.
The company said ReWalk costs the centers about $90,000 each and is adjustable for a range of sizes. The personal version that fits only one user is expected to cost at least $65,000 and include training. If there are proven benefits, insurers would be more likely to cover some of the tab. And supporters say that within a half-dozen years, the suits could become ubiquitous on the streets, as paraplegic people use them to walk to work, go shopping, etc.
In 2012 a paralyzed British woman used a ReWalk exoskeleton to finish a marathon, though it took her 16 days. Many Americans may have learned of it when the character Artie Abrams got one for Christmas on the Fox television show "Glee."
Clinical trials are underway to gauge the health benefits, but company officials believe patients in wheelchairs see improvements in bone density, bowel and bladder movement, cardiovascular health, as well as a reduction in pain and spasms.
Turnage said the exoskeleton gives her relief from stomach pain for up to a day after a session. She's also relieved of bladder troubles.
If the health benefits aren't lasting, supporters say, there still are merits to standing and being independent. Just reaching a top shelf can be a big deal, Argo officials said.
"We are following the dream of our founder, Amit Goffer, who looked at the wheelchair he was in and noted that over thousands of years, there hadn't been any better alternatives," said Pete Escallier, Argo's vice president of sales, "and he set out to make one."
Jose Luis Contreras-Vidal is a professor of electrical and computer engineering and biomedical engineering at the University of Houston and teaches a class on such robotics. He called the exoskeletons potential "game changers."
The version that's been on the market the longest is HAL, or Hybrid Assisted Limb, created by Japan's Cyberdyne. It's been used in hospitals since 2008. But Contreras-Vidal said the technology is too new to fully understand the benefits.
And he said the next generation will likely be lighter and less bulky — some systems weigh up to 80 pounds — and may allow for more agility. They could also come down in price from up to $150,000 to a low of $30,000 — the price of a high-end wheelchair.
Contreras-Vidal has contributed technology to three systems and is currently working on how to use brain signals from noninvasive sensors to control an exoskeleton. Spinal cord injuries cut off the communication temporarily or permanently between the brain and the rest of the body.
"All of the systems are designed in a slightly different manner," he said. "We don't know yet which system is best and for whom. We have many questions. …We think they can have a very positive impact on the well-being and health status of a person. But it's going to take some development."
The exoskeletons could also reduce the cost to treat common maladies for someone in a wheelchair. Contreras-Vidal said a 35-year-old who becomes a paraplegic could generate $3 million in lifetime expenses for treatment and care. Costs can reach $5 million for younger people and could grow with life expectancies, according to the National Spinal Cord Injury Statistical Center.
The center reports there are about 12,000 new cases of spinal cord injury a year, and up to 332,000 living with an injury. A new study from the Johns Hopkins University found that injuries are on the rise and the leading cause is no longer car crashes, but falls, primarily among older people.
The Veterans Administration has been experimenting with the suits to help service members injured in war. Maryland Rehab & Ortho clinicians visited a hospital in the Bronx, N.Y., to see ReWalk in action before buying in. Maryland now has two $80,000 machines and plans to acquire two more for research.
Maryland officials also considered an exoskeleton developed by Berkeley, Calif.-based Ekso Bionic, which is used by Walter Reed National Military Medical Center in Bethesda.
NASA is testing a suit called X1 developed with the Florida Institute for Human and Machine Cognition. It could help astronauts with both surface exploration and exercise when there is no gravity or resistance against leg movements.
Still, the exoskeletons aren't for everyone. Dr. Henry York, director of the spinal cord unit at the Maryland rehab facility where Turnage is treated, said many suits like ReWalk require upper body strength and coordination for crutches. And at first, he wasn't sure Turnage could use one with her prosthetic leg, which wasn't designed for weight.
But her health was good and her will was strong, so York said he didn't want to say no.
Turnage couldn't be happier that she got a chance. Her 7-year-old daughter, Mikaela, has already seen her walk. And on Friday, she expects to stand and give her husband, Gabriel, a hug. He's in the military and has been traveling for much of her therapy, though they live on base at Fort Meade.
The family moves to Tennessee next month, and Turnage said she will continue to live a full life filled "with joy" without walking. She is a wife and mother, and for now, a part-time student studying cybercrime and a full-time administrative worker at a health care firm. There are travel and sports, much of which she began after coming to Maryland last year to ask about new research on treatments for spinal cord injuries.
She would still like to try sky diving. But what she really wants to do sometime soon is "go for a walk with my family."