Popsugar Health & Fitness Dumbbell Workouts 21-Day Butt-Building Challenge Our 21-Day Booty Gains Challenge Is Here to Build Your Backside 23 March 2018 by Susi May View On One Page Photo 1 of 6 ADVERTISEMENT () Start Slideshow Share This Link Copy ← Use Arrow Keys → 1 Click here for a printable PDF of the challenge. Previous Next Start Slideshow Dumbbell WorkoutsButt WorkoutsFitness ChallengesStrength TrainingWorkouts