(ABC News) -- As runners are striding the 26.2 miles from Staten Island to Central Park for the 43rd annual New York City Marathon today, one family waiting at the finish line couldn't be prouder of what their two sons are accomplishing.
Identical twins Alex and Jamie Schneider, both 23, are severely autistic, but running has given them joy and relief from the frustrations of not being able to communicate.
"In the spectrum, they're at the very bottom. Both of them are non-verbal," the twins' mother, Robyn Schneider, told ABC News. "[Running] is our number one main activity as a family. Everything else kind of comes second."
When the boys were eight years old, their father, Allan Schneider, noticed how much they enjoyed chasing him around. By the time they were 15, the Schneiders realized the boys were born to run.
"We actually found out about a club that offered volunteers to run with individuals with disabilities," Robyn Schneider said. "They said, 'These guys are amazing.'"
The twins have been racking up medals ever since. In total, Alex and Jamie Schneider have run about 130 races, from 5Ks to marathons, and everything in-between, their mother said.
Both boys have to run with the assistance of a guide, but when it comes to running styles, the twins approach the sport differently.
"[Alex ] is born to run. I have to cheat on the off-days when we don't run together," his running coach, Kevin McDermott, told ABC News. "I'll sneak in four or five miles just so I can stay in good enough shape [to keep up with him]."
For Jamie Schneider, who runs with his dad, hitting the pavement is about the experience.
"Jamie will stop at every single water stop. He'll want to shake hands with people," Robyn Schneider.
"I'll explain to people, there's not a lot I can share with him, but when we're running, it's an unspoken language," Allan Schneider said of running with his son. "It's been wonderful."
Both Alex and Jamie Schneider are running the New York City Marathon for the first time.
The twins are running for the Association for Science in Autism Treatment to raise money and awareness for the non-profit dedicated to the education and care of people with autism.
Both ran in the Boston Marathon earlier this year. Alex Schneider is hoping to beat his personal best time of three hours and 23 minutes, which he set at the April race, while Jamie is hoping to cross the finish line.
"They don't have a normal life, so [running] is something that really, I think, connects with them, and makes them happy," Allan Schneider said.