AP Photo/Charles Krupa

WATCH: Marine Heroically Crawls over Boston Marathon Finish Line

"Do I have my legs? Do I have arms? Where am I bleeding?"

Back in 2010, the "Lava Dogs" division of the United States Marine Corps was hit with a 50-pound improvised explosive device (IED) while in Afghanistan. Lead machine-gunner Micah Herndon was thrown from his seat during the explosion, knocked unconscious, and suffered several injuries. Incredibly, that was the third time Herndon's Lava Dogs marine division was targeted with an IED during his deployment.

The first was a 400-pound explosive that killed two marines, Mark Juarez and Matthew Ballard, as well as British journalist Rupert Hamer, who was traveling with Herndon's division. After returning to the United States, Herndon took up running as he healed his wounds — both mental and physical — while remembering the friends he lost every step of the way.

Herndon started running three miles a day and became addicted. The First-Team All-Section football and basketball player in high school entered his first half marathon in 2017. He placed 16th out of 2,272 runners at the Pro Football Hall of Fame Marathon in his home state of Ohio. The next year, he finished 15th.

After training to run a full marathon, Herndon qualified for the prestigious 123rd Boston Marathon with plans to honor the friends he lost during his service.

"I run in honor of them. They are not here anymore. I am here, and I am able. I am lucky to still have all my limbs. I can still be active. I find fuel in the simple idea that I can run. Some cannot.

"I feel like if I am not running, then I am doing something wrong with my life. If I get a heat cramp while running or my feet hurt or I am getting exhausted, I just keep saying their names out loud to myself. They went through much worse, so I run for them and their families."

— Micah Herndon, h/t The Record-Courier

As Herndon approached the finish line of the Boston Marathon, he collapsed to the ground with leg cramps. He was still 100 yards — the length of a football field — away from finishing the race. For those of us who'd never heard of Micah Herndon before, what he did next told us everything we need to about him.

Herndon crawled across the Boston Marathon finish line, later saying that his combat training kicked in on instinct, and he finished with a time of three hours and 38 minutes.

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What gave him the Marine veteran that final surge of energy before needing a wheelchair and medical attention? The people he lost.

"I say their last names out loud while I'm listening to my music," Herndon told CBS News in Boston. "I just repeat: 'Ballard, Hamer, Juarez. Ballard, Hamer, Juarez.'"

The red running shoes Herndon wore for the race even had gold plates with the names of those three men as a reminder of why this heroic Marine was running in the first place.

There are hundreds of inspiring stories from the Boston Marathon. Lawrence Cherono of Kenya won the men's race by only two seconds, which was the closest finish in 30 years. Worknesh Degefa of Ethiopia won the women's race in a runaway by almost three minutes. The races are filled with incredible athletes who run 26.2 miles in mind-blowing times, but Micah Herndon's race is this year's best.

The American from Tallmadge, Ohio wasn't running for glory or the prize money. He was doing it to honor his friends who died overseas. That courage he showed to finish the damn race is incredible, and now it should be the rest of us who are honoring Micah Herndon for what he did.

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