Slider Ab Burnout Tone your abs and shoulders with this key move. Begin in a plank position with your hands on the ground and a slider under each foot. Maintaining a straight line from head to toe, engage your core and slide your right foot in toward your chest. Slide your left foot to meet your right. Then, slide your right foot back to start position, followed by your left. Perform three sets of six to eight reps per side. Image Source: Tone It Up