Works the back, glutes and thighs.
Lie on the floor on your back. Bend both knees and place your feet flat on the floor. Keep your hands alongside your hips. Now slowly raise your hips off the floor, lifting them till they are in line with your knees or higher. Squeeze your thighs, butt and back as you lift. Gently lower and just before you touch the floor, lift up again.
Do 16 reps, rest and repeat.
Photograph: Carlo Allegri/Getty Images
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