Start sitting on the ground facing the landmine attachment with your legs open for stability while holding the end of the bar in a neutral grip with your hand resting at your shoulder and your elbow beneath your wrist.
Leaning forward slightly, press the bar up into the air until your arm is fully extended. At the top of the movement, switch which hand is holding the end of the bar and lower the bar back down to the opposite shoulder. Perform again to return the bar to the starting position.
Repeat for the desired number of reps.