Your A-to-Z Guide to a Flat Belly
T-Try a harder plank
Increase the belly benefits by replacing your usual plank pose with this variation, recommends Stuart McGill, PhD, author of Ultimate Back Fitness and Performance. Kneel and put forearms on a stability ball, elbows bent and hands clasped; roll forward and straighten legs behind you. Move the ball in little circles with forearms, keeping the rest of your body still.
Next: U-Unhook that bra