Trainers discuss how long it takes to get visible ab muscles—which has more to do with healthy habits than a simple plan.

If you have 10 minutes to spare, you have enough time to tackle this effective core workout that puts you through two rounds of fast-paced exercises to target your upper and lower abs.

Your core (that means both your back and abdominal muscles) is your source of power—seriously. It's also what helps stabilize your entire body, prevent low back pain, and impact your posture, helping ...