15 Simple Yet Effective Ab Exercises You Can Do at Home

Planks are hard enough, but if you want to really work your obliques, add in this side crunch.

• Come into a side plank on your right side, with your feet stacked one on top of the other and your weight on your right elbow, palm down.
• Place your left arm behind your head, and inhale to prepare.
• Exhale and pull your navel to your spine to engage your deep abs, then rotate your left rib cage toward the floor.
• Stay there for a second, and deepen your abdominal connection by pulling your navel in toward your spine even more.
• Return to the starting position. That's one rep.