Popsugar Fitness Workouts Standing Core Exercises Farewell, Crunches — Do These 11 Standing Exercises For Tighter, Stronger Abs October 13, 2020 by Tamara Pridgett View On One Page Photo 3 of 12 ADVERTISEMENT () Start Slideshow Share This Link Copy ← Use Arrow Keys → 3 High Knees Hold your hands at waist level. Hop the right knee up toward your hands, then quickly switch legs and hop the left knee up. This counts as one rep. Previous Next Start Slideshow WorkoutsStrength TrainingCore ExercisesTrainer TipsAb Exercises