Two young New Yorkers who overcame traumatic brain injuries — including one who had to relearn how to walk — are using their new lease on life to run in Sunday’s city marathon.

Alexa Casciano, 24, and Christian Longo, 26, are both joining the beastly race to benefit the Brain Injury Association of New York State in honor of other TBI victims who aren’t able to make the 26.2-mile trek.

“The ability to walk, I find that people take for granted. But we have legs, and we complain about how many flights of stairs and all that stuff,” Longo said.

“Why are you complaining about things like that? You should be caring that your legs can handle climbing up those many stairs. Those are things that I always remind myself of because they really can always be worse.”

Completing the New York City

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