Ahh today's workout involved over 300 Squats and lots of AbMat sit ups. What does the abMat Do? Positioned under the lower back, the contoured AbMat enables a full extension of the abdominals at the beginning of a sit-up by tilting the spine, which is not possible on a flat surface. ... The result is a more efficient and complete core training of the abdominal, oblique, and back muscles. I highly recommend using one. I finished off with some oblique work. I'm not quite there but am trying to get my core stronger than ever. I'm back on Monday for my classes.