Power Armor is a plank-based core workout that never lets you off the floor - and never lets your core stop working. The entire round takes place in plank position, moving between leg raises, crunches and holds without ever standing up. Plank leg raises lift one leg at a time while your core fights to keep your hips level and your lower back from sagging. The 10-count holds between each exercise aren't recovery - they are the challenge, asking your shoulders, core and glutes to maintain a strong, still position under accumulated fatigue. Plank crunches bring the knees toward the chest from plank, adding hip flexor and deep core work to everything else already happening.

The pattern repeats: move, hold, move, hold. Each time you return to the hold, your body has a little less left to give - and that is exactly the point. The holds build the kind of core endurance that doesn't just show up in workouts but carries over into everything else you do.

Power Armor builds your core the way good armor is made - layer by layer, until nothing gets through.