On Memorial Day weekend 2007, Dr Joshua Appel had an idea.

The American holiday, held at the end of May, had become associated with beers and barbecues. But Appel, then a medical resident in Albany, New York, wanted to remind himself and others of the day’s original purpose – he wanted a way to contemplate with mind and body those who had lost their lives in military service.

Appel had recently begun to train at CrossFit Albany. “I heard about this Hero Workout of the Day called Murph,” he says. Hero WODs are dedicated to a military member or first responder killed in the line of duty. “And I was, like, ‘I wonder if that’s the same Murph.’”

It is one of CrossFit’s hardest workouts, a prolonged thresher that blends endurance and calisthenics with a whole lot of time in your head, beating back millennia of human wiring telling you to slow down or tap out. It goes like this: you run one mile, do 100 pull-ups, 200 press-ups and 300 squats, then run one more mile – all as fast as possible, while wearing a weight vest.

Appel was not a typical medical resident. He had been involved in the military since 1994 as an air force para-rescueman; he was a combat search-and-rescue specialist trained to retrieve wounded service members. He enrolled in medical school in 2001. “I graduated on 11 May 2005,” he says. And that’s when things got hot. He was on a plane to Afghanistan two days later. “Then, on June 28, we got the call that the Chinook [helicopter] had been shot down and a Navy SEAL team was missing.”

Operation Red Wings went as tragically as a mission can. Early that morning, the military dropped four SEALs – Lieutenant Michael Murphy and Petty Officers Danny Dietz, Matthew Axelson and Marcus Luttrell – about 3km high in the Hindu Kush Mountains. The team was to provide reconnaissance for an impending action against the guerrilla leader Ahmad Shah.

The plan twisted southward when some goatherds stumbled on the team’s position. Within hours, the SEALs were taking fire on three sides by a force of more than 50 anti-coalition militiamen. The SEALs, all wounded, were pinned against cliffs, which blocked the signal they needed to make a distress call. Understanding his team’s predicament, Murphy, according to the US navy, “unhesitatingly and with complete disregard for his own life moved into the open, where he could gain a better position to transmit a call to get help for his men… This deliberate and heroic act deprived him of cover and made him a target for the enemy… He was shot in the back, causing him to drop the transmitter.” Murphy picked it back up and completed the call.

Murphy, Dietz and Axelson died on that mountainside – as did the 16 special forces service members whose helicopter was shot down while racing in to extract the four SEALs. Luttrell escaped. Locals discovered him and carried him to a village, where they kept him for three days. Luttrell’s story is told in the book and movie Lone Survivor.

“I was the para-rescue team leader who rescued Marcus Luttrell and recovered Michael Murphy and Danny Dietz,” Appel says. He kept the body armour he wore when he recovered Murphy’s body. Two years later, after he’d started CrossFit and realised that the Murph workout on the board was, in fact, the same Murph, he approached the owner of Albany CrossFit and said, “We should get everyone together and do a Hero Workout on Memorial Day.”

Appel suggested Murph. “We had

13, maybe 15 people. I thought it would be cool if everybody did Murph, so everyone has the same goal.” He wore his body armour.

“It was very unifying and brought all kinds of people together,” Appel says.

THE NAVY SEAL WHOSE DEATH INSPIRED THE MURPH