Understanding pelvic alignment in exercise should be a priority for anyone seeking to maximize the effectiveness of the moves they do. The alignment of the pelvis effects everything above and below it, from the alignment of the spine and neck to that of the legs and feet.
Tucked pelvic alignment is associated with poor posture, back pain, and at the least, inefficient movement patterns. When we over tuck the pelvis, we engage a set of muscles including our hip flexors, glutes (butt muscles) and quadriceps in a way that creates an inefficient, and potentially injurious, alignment of the pelvis.
In Pilates instruction, there is some variation about whether to do certain exercises with a flat back or a neutral spine. Some Pilates exercises are done in way that allows the back to lengthen along the mat in response to the engagement of the abdominal muscles creating a slight tilt of the pelvis. But this is not the excessive tuck that is getting in a lot of people's way. There is not much debate, however, about the overly tucked pelvis. It won't work.
On this page, we take a close up look at the neutral pelvis, and on the next page, the overly tucked pelvis. I think you will be able to see the difference. In the photo above, our model has a neutral pelvis. Neutral is generally the most efficient and natural alignment for the pelvis, whether you are standing, sitting, or lying down.
To see that our model's pelvis is in a neutral alignment, notice that if a plate were set on her lower abdomen, it would lie flat, not tilting down or up. If she were to take this position standing, you could imagine that her pelvis was a bowl of water and that the water sit evenly and not slosh out to the front or the back.