This is part of CNET's "Tech Enabled" series about the role technology plays in helping the disability community.
Wayne McDonald is one of the roughly 4 million people in the world who does CrossFit. A few times a week, he goes to classes not far from his home near Akron, Ohio, and works with a coach who helps him with the rigorous fitness program.
For anyone, CrossFit -- which combines elements of running, weight lifting, gymnastics and more -- can be grueling. For McDonald it's something of an achievement, since he lost his left leg above the knee in a motorcycle accident back in 2007.
"[It's] been interesting and exhausting and everything else because with two legs I would not have been particularly good at it," laughed McDonald, who created a website called Amputee Guy about his experiences.
McDonald might not have summoned the courage to start CrossFit if not for the help of a app called Fitness for Amputees, designed for lower-limb amputees.
Fitness for Amputees is just one in a budding group of mobile apps that have sprung up to help speed the recovery process for people who've lost a limb. There's ample demand for such services; in the US, nearly 2 million people have lost a limb, according to the nonprofit organization Amputee Coalition.
Depending on the limb and the point of amputation, amputees can face a variety of challenges just trying to return to the everyday functions others take for granted. But in the mobile age, when we spend so much time on our phones posting photos on Instagram and streaming video on Netflix, it's a no-brainer that there are fitness apps designed to help amputees learn to walk straight, control their prosthetic limbs and, yes, get in some CrossFit.
"Just like the general population, we are seeing large numbers of people accessing resources and making connections with mobile," said the Amputee Coalition's chief communications officer, Karen Lundquist.
McDonald's Fitness for Amputees app came from Ottobock, a company that and runs clinics around the world.
The app, launched in 2014, targets strength (particularly the muscles you use in your trunk to hold yourself up), balance, coordination, and stretching (to help prevent muscle contractions) -- all areas necessary to get a person not only moving, but also moving the right way again, said Ottobock's head of sales and marketing support in Germany, Anne Debusson.
In trying to figure out how to help amputees when they might have limited access to rehabilitation and therapy, Ottobock realized it could use mobile to deliver important fitness training.
"The app was just the perfect medium for it," Debusson said.
Aside from the main goals of improving strength and balance, the app also plays a role in boosting confidence, McDonald said. He used it for about four months prior to taking up CrossFit. He also appreciates that the app has exercises he can do with and without his prosthetic: If he was dealing with soreness or skin irritation, he didn't have to skip his workout. And that's something he's mindful of, noting that many amputees (nearly half, according to one study) have vascular issues.
Eventually, McDonald was ready to move on.
"I felt more comfortable signing up for CrossFit and things like that," he said. "I didn't feel like I was going to be totally incompetent. It helped me more mentally, even, then it did physically, which is no small thing."
Walk this way
CrossFit may or may not be an end goal for lower-limb amputees. Regardless, they'll have to spend time just working on getting their walk correct again.
The University of Miami's Frost School of Music, Miller School of Medicine, and College of Engineering are working on a mobile app called ReLoad to help people do that.
Learning to walk symmetrically with a prosthetic device can be challenging, but it's important because otherwise amputees can develop knee and back pain. Plus, the likelihood increases the higher the amputation, said Bob Gailey, professor in the University of Miami's Department of Physical Therapy.
ReLoad uses verbal instructions and music to help correct an amputee's gait, based on data from sensors in a knee sleeve worn by the amputee. So, for instance, if people aren't walking evenly, the music will warp and they might hear a command to roll over their toe or move their hip.
"We're trying to give a person a gait lab in their pocket for just a few hundred dollars," Gailey said.
An amputee might be invited to a gait lab at a university or research center, but it's not common. Gait labs are more for research purposes, not physical therapy. In such a lab, an amputee would walk in a straight line while cameras collected precise data about things like the angle at which the knee bends. It's also rare that amputees would get to run through all that data for their own benefit.
With ReLoad, part of the idea is that amputees could just take a casual walk while practicing their gait -- and to tunes like "Walk This Way" by Aerosmith.
"When you suffer an accident, your emotions are all over the place," said Jennifer Lopez, a Miami-based nurse who lost her leg in an accident three years ago. Lopez got to try out ReLoad. "What's nice is [the music] kind of helps you disconnect, but at the same time the music therapy helps you identify if you do have any deviation from your gait."
Gailey also sees the app as a way to help those whose insurance might cover only a limited amount of physical therapy sessions. ReLoad could help make therapy cheaper and more effective when combined with rehab sessions.
ReLoad's been in the works for five years. Gailey and his team are working with the Department of Veterans Affairs and the Department of Defense and are testing it out with service members and veterans at Walter Reed Hospital as part of a clinical study. The next phase will be expanding ReLoad to hospitals around the country.
Getting a grip
When Jason Koger woke up from a three-day medically induced coma, he had to come to terms with the fact that he no longer had hands.
While riding an ATV in 2008, he came into contact with a downed power line and took 7,200 volts of electricity. Doctors had to amputate his hands to save his life.
"At the time, I thought, 'What are the chances of me ever being able to dress myself or feed myself much less be the dad that I wanted to be?'" Koger said.
After a decade and a lot of hard work, Koger's regained a lot of what he lost thanks in part to Touch Bionics' i-limb.
The i-limb, which came out in 2007, was the first prosthetic hand with a motor in each finger, said Nathan Wagner, prosthetist-orthotist and occupational therapist at Touch Bionics. That's what really drove the need for an app. Several iterations later, the i-limb quantum lets users program and access different grips using an app that connects to the prosthetic via Bluetooth.
So if a user needs to grasp a spray bottle, for example, getting to that grip is a tap away. And what's more, since the i-limb uses an accelerometer -- the same technology that helps your smartphone switch between portrait and landscape -- users like Koger can program hand positions to trigger certain grips.
As a result, Koger can complete tasks as delicate as cracking an egg.
The app also lets him see data about how he's moving his muscles, and he can also send diagnostics back to his prosthetist. The ability to send that data and have the prosthetist make changes could save him a long journey.
Getting the i-limb wasn't easy. Koger said it took convincing his insurance company that hooks wouldn't be good enough.
Koger's dexterity has gotten him a lot of attention. He appeared in Apple's 30th anniversary commercial, as well as in an episode of the CBS drama "Hawaii Five-0" in which a villain needed a pair of bionic hands.(Disclosure: CNET and CBS share the same corporate parent.)
"These are definitely not my original hands," he said, "but it's the closest thing that they've got."
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