Get ready to work your lower body and strengthen your core with this beach-friendly move. Part of our Fun-in-the-Sun workout, this exercise uses a simple beach ball to target and work ab and back muscles you probably don’t know you have. So simple, yet so challenging!

How to do it: Lie on your right side with the arms pointing overhead and a beach ball placed between your feet. (As shown in the photo above.)

Photo: Joseph Montezinos

Next, lift the legs off the ground while simultaneously lifting your upper body and twisting your torso to reach the left arm toward the feet. Use your right arm to steady your body, but focus on engaging the abs.

Return to starting position. Do 10 reps, then switch onto your left side and repeat.

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