Disabled Sports USA writes about handcycling:
Handcycling was developed in the 1980s by people working to create alternate types of human-powered vehicles. So it was almost by accident that a new world of cycling was opened to people with disabilities.
"It's ideal for people who have no or limited use of their legs, people who have poor balance, or anyone that just wants to try a different sport," said Heather Plucinski of Challenge Alaska. "It opens up a lot of trails and a lot of countryside, a lot of fresh air, and a lot of places you can travel. It's a great piece of adaptive equipment that allows people to get outside."
"The disabled community picked up on it right away," said Ian Lawless, Colorado regional director and cycling director for Adaptive Adventures. Even people with one working arm can handcycle with some modifications made to the equipment, said Lawless. "Just about anyone can do it. It's an accessible sport. It's not just for racing; it's also for recreational riding. It's a barrier breaker that allows a disabled rider to participate in cycling with friends and families who may be riding conventional bicycles."