Hard to the core
TIghten up that tummy and keep back pain at bay by working your entire core. This five-minute routine consists of another three-exercise AMRAP — do as many rounds as you can.
40 Bicycle crunches (20 per side)
Lie on the ground, your core tight, your hands next to your ears, your legs straight. Lift both feet from the ground, then bend your left knee, drawing it in toward your chest as you simultaneously crunch your shoulders up off the ground and twist your right elbow toward your left knee. Immediately reverse the movement, before drawing your right knee in toward your chest while crunching your left elbow toward your right knee. Continue this “bicycling” movement with your legs as you work your obliques with the side-to-side crunches.