Popsugar Health & Fitness Workouts Butt and Ab Workout This Bodyweight Butt and Ab Workout Is So Good, You'll Cancel Your Gym Membership 23 January 2019 by Tamara Pridgett View On One Page Photo 3 of 5 ADVERTISEMENT () Start Slideshow Share This Link Copy ← Use Arrow Keys → 3 Plank With Clamshell Lie on your left side with knees slightly bent and your elbow underneath your shoulder. Press into your bottom forearm to lift the hips as high as possible, keeping your abs engaged. Raise your top knee to open the thighs like butterfly wings, then slowly lower the knee, completing one rep. The move is similar to the clam. Complete 10 reps on each side. Previous Next Start Slideshow Trainer TipsBooty Gains15-Minute WorkoutsButt WorkoutsBeginner WorkoutsBodyweight WorkoutsIntermediate WorkoutsCore ExercisesAb WorkoutsStrength Training