Popsugar Fitness Under Armour 20-Minute Booty Burn Workout Try Under Armour's 20-Minute "Booty Burn" Workout to Enhance Your Derrière August 30, 2021 by Angelica Wilson View On One Page Photo 4 of 5 ADVERTISEMENT () Start Slideshow Share This Link Copy ← Use Arrow Keys → 4 Single Leg Kickback Start on all fours with your knees under your hips and hands under your shoulders. Lift your left leg and flex your foot as you kick it back behind you and straighten your leg. Return to the starting position. Repeat on the same side for 20 seconds, and then switch to the other leg for the final 20 seconds. Rest for 10 seconds. Previous Next Start Slideshow Under ArmourWorkoutsStrength TrainingHome WorkoutsBodyweight ExercisesBodyweight WorkoutsButt WorkoutsButt Exercises20-Minute Workouts