The Chair Bird Dog exercise works your abs.
You Can Do It, Lose 10, 15, 20 Pounds. Chair Bird Dog: With your palm flat on the seat, inch forward so that your hips slide off and then extend 1 leg and the opposite arm forward. The key here is to keep your abs nice and tight. Hold for 1 to 3 counts then lower your arm and leg and repeat. You're going to do 8 to 10 reps then switch sides and do another set.