Start in a push-up position with your hands under your shoulders. Shift your weight onto one hand, peel the other off the floor, and rotate your whole body open into a side plank - feet stacking or staggering as your free arm reaches straight up toward the ceiling. Hold for a moment, rotate back down to the plank, plant the hand, and open to the other side. The body turns as one piece, hips and shoulders together, with no sag in the middle at any point of the turn.

Works: obliques, abs, shoulders, lower back

Breathing: Exhale as you rotate open and reach up, inhale as you return to the plank.

Common Mistakes: Letting the hips drop toward the floor mid-rotation, turning the shoulders while the hips lag behind, and rushing through the top instead of pausing in the side plank.

Make Easier: Stagger your feet wide for a steadier base and shorten the reach, or build the pieces with Shoulder Taps and Side Bridges.

Make Harder: Hold the side plank for a three-count on every rotation, or move on to Side Plank Rotations or Up & Down Planks.