This Memorial Day weekend, thousands of fitness enthusiasts like myself will remember the fallen by participating in a workout simply known as Murph.

The workout is named after Lt. Michael P. Murphy, a Navy SEAL who was killed in action in Afghanistan in 2005. Murphy made the ultimate sacrifice. When his team was compromised and surrounded by Taliban fighters, he left cover and moved into an open clearing—exposing himself to enemy fire—to get a signal on his satellite phone. He was able to contact headquarters, relay their position, and request help. His selfless actions cost him his life, but saved others.

When Murphy originally created the workout, it was called ‘Body Armor’. It wasn’t until August of 2005 that CrossFit founder Greg Glassman posted the workout to CrossFit’s website as the Workout of the Day (WOD). 

Since then, Murph has grown in popularity every year. What started within the CrossFit community and among military service members has expanded to boot camps, global gym chains, and even people working out in parks or neighborhoods. It’s a workout that brings people together for a purpose far greater than fitness.

One reason Murph has caught on is its simplicity. It requires minimal equipment and can be scaled for any fitness level—while still offering a challenge. The workout goes like this:

1 mile run, 100 pull ups, 200 push ups, 300 air squats, 1 mile run while wearing a 20-pound weight vest. 

There’s some debate over how it should be completed. Some insist the reps must be done in order—100 pull-ups before moving on to push-ups, for example—while others prefer to partition the reps (like 20 rounds of 5 pull-ups, 10 push-ups, and 15 air squats). Either way, the goal is the same: honor the sacrifice.

If you’re just beginning your fitness journey or coming back from injury, there are plenty of ways to participate. You can scale the volume with a Half Murph or Quarter Murph. If you can’t run, sub in a bike or rower. If you’re not ready for pull-ups, do ring rows. Push-ups too difficult? Try incline push-ups. No pull-up bar? Do sit-ups instead. The workout is infinitely adaptable.

You can also officially register for The Murph Challenge at www.themurphchallenge.com, with proceeds benefiting the Murph Foundation.

If you’re interested in learning more about Lt. Murphy and his mission, check out the book Lone Survivor or the 2013 movie adaptation starring Mark Wahlberg. There’s also a documentary-style film called Murph: The Protector available on Amazon, which shares his story through the voices of his family and friends.

However you choose to spend this weekend, take a moment to remember those who gave everything.

Brandon Brigman is the owner of No Excuses CrossFit in Suwanee. For 15 years, he has helped more than 1,000 people improve their fitness and nutrition through group classes and personal training. For more information, visit www.noexcusescrossfit.com.