PopsugarFitnessWorkouts7-Day Ab Challenge From Tone It UpWant a Strong Core? This Week-Long Ab Challenge From Tone It Up's Stef Corgel Is For You January 5, 2021 by Samantha Brodsky View On One Page Photo 7 of 7 ADVERTISEMENT () Start Slideshow Share This LinkCopy ← Use Arrow Keys → 7PreviousNext Start Slideshow WorkoutsHome WorkoutsTone It UpAb WorkoutsFitness ChallengesDumbbell Workouts