SETUP: Get into a PLANK Position with your elbows positioned on the floor directly under your shoulders. Hold a straight line with your body by keeping your abs tight.
REP: Take a dumbbell in one hand (must have circular weights, so it can roll!), and push it out in front of you until one arm is fully extended, then roll it back.
TIP: The hardest part of the rep here is when the weight is out in front, as your abs, lower back, and even your hip flexors will need to work double time in order to stabilize you. Make sure to press in a slow, controlled tempo so you don’t skip the hardest fucking part of the rep.