As Memorial Day rolls around, most people have images of beaches and barbecues dancing in their heads. CrossFitters, on the other hand, get ready for the unrelenting strugglefest that is the “Murph” WOD. It’s a simple workout that’s done for time: a one-mile run, 100 pullups, 200 pushups, 300 squats, and another one-mile run—while wearing a 20-pound weighted vest.

The workout was named in honor of Navy SEAL Lt. Michael P. Murphy, who was killed in Afghanistan in 2005, and posthumously awarded the Congressional Medal of Honor. He was known to do the workout in body armor, which the vest is meant to replicate. For CrossFitters, the Memorial Day Murph has become an annual tradition.

Even if you opt to do it with just your bodyweight and break the reps in the middle up into sets, completing a Murph is no walk in the park. Those hardcore enough add the 20-pound weighted vest, and true badasses do it straight through, no alternating between pullups, pushups and squats.

The final variation is what Hunter McIntyre, a force to be reckoned with in obstacle course racing world, will be doing on Saturday, May 23 at 6:30 a.m. EST in an attempt to break the current world record. Obstacle Racing Media provided live coverage of the event. Check out the full video below or on their YouTube Channel here.

There’s no Guinness World Record listing for the fastest Murph, but Björgvin Karl Guðmundsson completed the workout unpartitioned in 38:40 at the 2015 CrossFit Games, and his time is widely accepted as the world record. At the 2016 CrossFit games, Josh Bridges and Mat Fraser completed partitioned Murphs in 34:38 and 35:48, respectively.

McIntyre, an absolute maniac, is gunning for a sub-30 time, he said in one of the installments of his “Making Murph” video series. His attempt will be judged by Chris McNamara of Evolution Athletics.

Matt B. Davis, co-founder of Obstacle Racing Media and longtime industry insider, is our man on the ground for the event, which is happening in Fort Bragg, NC. Tune in to ORM’s YouTube channel for live coverage as the event unfolds.

Follow ORM on Instagram at @obstacleracingmedia, and follow Davis at @mattbdavis.