Popsugar Fitness Workouts 3-Minute Plank Workout Tone Your Arms and Core With This 3-Minute Plank Workout January 9, 2016 by Jenny Sugar View On One Page Photo 3 of 5 ADVERTISEMENT () Start Slideshow Share This Link Copy ← Use Arrow Keys → 3 Side Plank Crunch Lower into a side elbow plank with your left elbow down and your right hand behind your head. Keeping your torso stable and your waist lifted, bring your right leg up toward your shoulder to lightly tap your right elbow. Lengthen your right leg back to the starting position to complete one rep. Do as many reps as you can for 30 seconds. Then switch sides for another 30 seconds. Previous Next Start Slideshow WorkoutsStrength TrainingBodyweight WorkoutsAb WorkoutsBeginner Workouts5-Minute WorkoutsArm Workouts