4 Weeks to Flat Abs
(works central abs, plus inner thighs)
Start lying down with knees bent and legs together, feet pressing into mat. Hold ball between hands above chest. Curl chin to chest and roll up, rounding over knees and reaching arms and ball out over legs. Slowly roll back down, keeping ball in front of chest, legs bent and together. Do 6–8 reps.
Trainer tip: To make this move easier, do without the ball; to make harder, hold ball between knees.