Most of us with full-time jobs are told to call in sick if we ever develop an illness or hurt ourselves outside work.
But when you work as a special forces soldier in the field, calling in sick is never an option.
Some, including Master Sergeant Scott Neil Master's mate Tony Pryor, took this to another level.
The US Green Beret once killed four enemy soldiers - taking down the final man in hand-to-hand combat while suffering from a broken collarbone.
Master described the incident involving his friend on YouTube podcast The Pat McAfee Show.
He said: "I had a friend Tony, he was the army powerlifter of all of Europe, his fingers were the size of this water bottle right here."
He went on to describe how Tony killed four enemy soldiers in quick succession - the last one in hand-to-hand combat with a broken clavicle.
Pryor described the incident in a 2003 bulletin called Special Warfare.
He recalled raiding a building controlled by enemy soldiers in Afghanistan.
When one combatant charged out, he took him down.
Then, after entering, he proceeded to eliminate the two men about to fire their weapons out the windows at his fellow soldiers.
Once inside, Pryor described feeling something behind him.
"I thought it was one of my teammates," he said. "That's when things started going downhill.
"There was a guy behind me and he whopped me on the shoulder with something."
His attacker then pulled Pryor to the ground and ripped his night vision goggle's off and tried to place his fingers in his eyeballs.
But the special forces soldier was too quick and managed to kill the fourth man too.
It was only after the fight he realised his collarbone was broken and he had dislocated his shoulder.
He was awarded a Silver Star for 'conspicuous gallantry and intrepidity in action' following his heroic actions.
Podcast host Pat McAfee said: "We had a guy who couldn't do a podcast because he broke his clavicle falling off a f***ing scooter."
Master himself was among one of the first special operators to enter Afghanistan following the 9/11 terrorist attacks.
He was involved in the operation to remove the Taliban from power in Afghanistan and extract any Al-Qaeda members from the country.
The US military then sent Master and his Expendable-type squad into Iraq.
After Iraq, Master was deployed in Africa to fight Al-Qaeda and other terrorist groups.
Words: Charlie Metcalfe