Is it possible to selectively train your lower abdominal muscles?

Based on electromyographic (EMG) activity recorded during the performance of various abdominal exercises (e.g., crunches, reverse curls, leg lifts), the upper and lower rectus abdominis act as one muscle group. Despite the common misconception, data shows that it's not possible to recruit the "upper" and "lower" abdominal muscles separately. Part of the confusion is the fact that during certain abdominal exercises (e.g., reverse curls, leg lifts), people experience localized muscle fatigue and discomfort in the lower abdominal region. This occurs because the primary muscle used in hip flexion, the iliopsoas, originates below the lower portion of the rectus abdominis. The key point to keep in mind is that the feeling of local muscle fatigue and discomfort should not be misinterpreted as specific recruitment of "lower" abdominal muscles.