Your Flat-Abs Handbook

Cardio for Killer Abs

To get show-off abs fast, Story Elizabeth Maley recommends doing at least three 30-minute cardio sessions per week, choosing activities that specifically target core muscles. Her top picks:

Best machines (500 to 600 calories an hour): Treadmill (run/walk hills), elliptical trainer with movable handles and rowing machine. Do 10 minutes of each machine, moving quickly from one exercise to the next so your core muscles are constantly challenged.

Best classes (350 to 650 calories an hour): Indoor group cycling, kickboxing, anything core board- or Bosu-based and most dance classes.

Best outdoor activities (300 to 450 calories an hour): Tennis, kayaking, volleyball, and surfing.

Originally published in Fitness magazine, June 2005.