Popsugar Fitness Summer 5-Minute Standing Ab Workout Rock Your Abs With This 5-Minute Workout June 24, 2018 by Susi May View On One Page Photo 1 of 5 ADVERTISEMENT () Start Slideshow Share This Link Copy ← Use Arrow Keys → 1 High Knees Hold one dumbbell at chest height and run in place while lifting your knees high to the level of your waist. Engage your abs as the knee comes up. Run for 30 seconds. Previous Next Start Slideshow SummerWorkoutsStrength TrainingAb WorkoutsBeginner WorkoutsIntermediate WorkoutsDumbbell Workouts5-Minute Workouts