Popsugar Health & Fitness Body Weight Bodyweight HVIT Workout This High-Volume Interval Training Workout Will Make You Sweaty For the Full 25 Minutes 29 November 2018 by Christina Stiehl View On One Page Photo 8 of 8 ADVERTISEMENT () Start Slideshow Share This Link Copy ← Use Arrow Keys → 8 Hollow Rock Flutter Kick Extend your arms straight back behind you and legs extend out. Lift up upper back and head while hovering legs off the floor, hollowing out your belly. Make sure lower back does not arch up. Flutter kick your feet for a count of 30. Previous Next Start Slideshow Body WeightFitness TipsBodyweight ExercisesInterval TrainingBodyweight WorkoutsWorkouts