Francesco Clark is standing.
It's something most of us take for granted, but for him, it's a big deal.
"Three years ago, I could only stand 20 minutes at a time," said Clark, 34, who injured his spine 10 years ago. "Now it's an hour and a half every day."
In 2002, Clark was 24 and had landed a dream job at a major magazine when he took a trip to a summer house just outside New York.
It was a perfect summer evening, and the pool was dimly lit.
Clark recalls the moment: It was as if the pool was begging him to dive in. Without hesitation, he listened.
His chin hit the floor of the pool.
"How can you describe knowing what (being) paralyzed feels like?" he said. "I lay underwater completely awake and completely conscious."
"The first thing I thought was, 'You're an idiot!'"
Approximately 1.3 million people in the United States are living with a spinal cord injury (SCI), according to the Christopher and Dana Reeve Foundation. Most of these injuries affect people between the ages of 15 and 35, the majority of them men.
Clark describes spending three years after his injury wallowing in guilt and self-pity. His desire to become who he used to be, he says, helped him find the will to not only move again -- but to move on.
Clark's recovery is documented in his book "Walking Papers."
In the intensive care unit, his prognosis was hopeless. Doctors told his parents that their son would live the rest of his life on a ventilator and never speak. There was no chance of him ever moving anything below his neck.
"The man next door to me was screaming for morphine because he was in the final stages of cancer," says Clark. "The thing that really scared me was that when I got in my room, he had a higher chance of living. It really made me fight."
He attributes this perseverance to his family and their unconditional support.
Clark's sister, Charlotte, had just graduated from college when he was paralyzed. She and the rest of his family have helped Clark battle his injury from the start.
"We've come to appreciate early on the small improvements that he makes because they become actually quite big," said Charlotte Clark.
"He'll be walking, I know he will be. When it's time, I know his body is going to be ready."
In the months after the accident, Clark pushed his health insurance provider to double his physical therapy sessions and cover more of his therapy equipment.
When doctors urged him to just accept that he would never move again, Clark defied the prognosis. Less than a year after his injury, he could feel his shoulders.
"I never wanted to believe that there would never be a cure for SCI. I was showing people how I already defied what my diagnosis meant. So why couldn't I push for more?"
Clark completes five hours of physical therapy a week. While standing, he does cardio for an hour and a half. He lifts weights in his garage.
He practices kicking his legs while playing a dance game with his niece. He undergoes electrical stimulation on his hands, legs and abs. On the weekends, he practices lifting his body off his bed. He describes his therapy like training for the Olympics.
He was tenacious, pursuing conventional therapies alongside less-proven ones. From stem cell surgery in Beijing to different clinical trials, Clark was fiercely determined to move again.
Dr. Manuel Avedissian, a research fellow involved with one of these clinical trials, refers to Clark as his "star pupil."