Andrew Kinard likes to stretch far back in his wheelchair and wrap his hands behind his head, revealing long twin scars that run the length of his muscled forearms like mottled ravines. It’s a casual pose, but one that took months of effort and dozens of surgeries to perfect.

“The fact that I can do this is pretty remarkable,” he said, smiling and wiggling his fingers.

Today, the arms that Kinard could barely lift from his hospital bed less than five years ago can power a handcycle wheelchair — a low-sitting, hand-pedaled bicycle — across the finish line at the Boston Marathon. His journey up Heartbreak Hill on Monday (April 18) was the culmination of months of training, mostly done on stationary bike rollers in the basement of his Harvard Business School (HBS) apartment building, sometimes on the 17-mile loop of the Esplanade when the weather was nice enough.

But it also marked the fulfillment of a promise Kinard, a J.D./M.B.A. candidate, made to himself not long after losing his legs: that the wounds he suffered in battle wouldn’t control his life.

“It’s a decision I have to make every day,” he said. “It never goes away, but it’s a commitment that I made.”

In October 2006, just six weeks into his first tour of duty in western Iraq, Kinard, a 23-year-old first lieutenant in the Marines, stepped on an improvised explosive device during a routine patrol. When he awoke a month later in a Maryland naval hospital, his legs were gone, and his chances of recovery were far from certain.

“My first thought when I woke up was, ‘Where’s my rifle, and what’s my dad doing in Iraq?’ ” he said recently, between classes at HBS, where he is studying this year toward his joint degrees in business and law.

Over the next several months, he endured 75 surgeries and agonizing pain. He was released from the hospital in April 2007 and devoted another year to intense physical therapy, learning to control the hands he almost lost and to care for himself in a wheelchair. He struggled to regroup after the military career he had trained for was cut short.

“The hardest part about it is sitting on the bench and watching the game go by,” he said of having to leave his fellow Marines in Iraq.

At a rehab session at Walter Reed Army Medical Center, Kinard had a chance meeting with Jim Haynes, J.D. ’83, then-general counsel to the Department of Defense (DOD). He decided to take Haynes up on an offer of an internship with the DOD’s Office of Legislative Counsel in Washington, D.C. Less than two years after his accident, Kinard was moving to a new city, working in a high-profile office, and living by himself.

“I knew that I could never just get settled, that I had to keep pushing the envelope,” he said. “I never really felt quite like myself until I started working again.”

The internship experience convinced Kinard he was cut out for law school, and in 2008 he applied to Harvard Law School. He was accepted and made yet another solo move to a new city.

“Growing up in South Carolina, Harvard was not even a word in my vocabulary,” he said. “It’s been an absolutely remarkable privilege to come here.”

Not content to merely endure the rigors of law school — and not intending, he said, to become a lawyer — he applied to HBS last year and is now in his second year of a four-year joint degree program.

Throughout his recovery, Kinard searched for ways to return to sports. An extreme-sports enthusiast who had played rugby at the Naval Academy, he missed the adrenaline rush and team spirit fostered by sports and in the Marines.

Kinard started handcycling in Washington in noncompetitive rides sponsored by the Wounded Warrior Project. (He is now a member of the nonprofit organization’s board of directors.) He connected with Achilles International, an organization that sponsors the Boston Marathon team of wounded veterans, and finished his first Boston Marathon last year with a time of 1 hour, 52 minutes.

“The beauty of an organization like Achilles is that they get guys interested in competitive athletics, reawakening that competitive spirit that is so often diminished after undergoing a traumatic, life-altering injury,” he said.

While he misses the camaraderie of team sports, he said, handcycling allows him to reawaken the warrior ethos he learned in the military, a side of himself he feared could have been lost in the accident.

“It’s encouraged, it is sought, it is cultivated,” he said. “Everything I did in the Marine Corps, both as a leader and with myself, was a competition.”

There’s another problem with marathons: For a guy like Kinard, they’re too easy. Despite a busy schedule that left little time for practice, he clocked in Monday at 1:37:32, improving on last year’s time by 15 minutes and earning a fourth-place finish out of 17 handcyclers. He’d like to train for longer races, such as Sadler’s Alaska Challenge, a 260-mile journey from Fairbanks to Anchorage, considered the toughest handcycle race in the world.

Kinard seems intent on focusing on the abilities he still has — a sharp mind, an intense competitive drive, those miraculously functioning arms — rather than the limits imposed by his disability. Otherwise, he joked, he’d be holed up in his apartment “with the shades drawn, crying and eating Ben and Jerry’s.”

“Keeping that in mind colors everything that I do,” he said. “I have to choose not to think about what I’ve lost, but instead be very thankful for what I’ve still got.”

Garber welcomed as provost