Standing Upright, hold a DB in each hand in a hammer hold. Keep your elbows locked at your side and have your forearms parallel to the ground, elbows at a 90 degree angle, straight in front of you. Retract your scapulas and back muscles as you open your arms laterally while keeping your elbows at your side as you march one leg up with control. As you lower that leg, bring your DB back to the starting position and contract your core and knit your ribs together. Repeat, switching which leg marches each time.