Upper Abs vs. Lower Abs

Question: What exercises can I do to target my lower abs?

Answer: There is no such thing as upper and lower abdominal muscles. They are collectively known as one muscle called the rectus abdominus. This is the muscle that most people associate with abs and the "six pack" muscle. There is a misconception that doing leg raises of other hip flexor exercises will target the lower portion of the rectus abdominus because of the fatigue feeling lower in the stomach. This fatigue is actually from the hip flexors which originate below the lower portion of the RA. So in short there is no way to target the lower abs. The entire muscle will be worked during all RA exercises. If you would like to see more definition on the lower part of the abs you need to concentrate more on your diet and cardiovascular exercise.

Source: www.acefitness.org