Popsugar Fitness Workouts Lower-Ab Workout Try Our 5-Minute Abs On Fire Workout June 27, 2016 by Susi May View On One Page Photo 1 of 5 ADVERTISEMENT () Start Slideshow Share This Link Copy ← Use Arrow Keys → 1 High Knees This exercise is great for warming up. It gets the blood flowing, but as you raise the knee up, you're working your low abs. Hold your hands at waist level and bring the knee up to your hands as you run. Do this for 60 seconds (c'mon, you can do anything for a minute). Previous Next Start Slideshow WorkoutsStrength TrainingIntermediate Workouts5-Minute Workouts