where do I even begin with my pelvic floor?

ASK A SWOLE WOMAN
This is the paid Sunday Ask A Swole Woman edition of She’s a Beast, a newsletter about being strong mentally/emotionally/physically.
The Question
I am 40 and two years postpartum, after carrying twins to term. Once I figured out how to carve a bit of time out of parenting twins life for me to work out, I spent six months doing core/pelvic floor rehab work. I had no acute, diagnosed injury, but twin pregnancy pushed me to the brink, and I wanted to proactively try to gain back some basic functionality before starting to lift or run. I felt better and was excited to move on to lifting after spending this time in the world of restorative exercise I am finishing stage two of LIFTOFF, and the other day, while doing an RDL, I felt a twang in my pelvic floor that just felt wrong. More than pain, it freaked me out. Am I bearing down when I lift and not even noticing it? Did pregnancy permanently break my body in some profound, yet low-key way? Should I even continue lifting? While the sensation remained off and on in a mild, achy way, this reaction was mostly emotional for me. I did stop lifting for a week, but then I started again. I guess my question is where to even start with lifting and also caring for my pelvic floor?
Grace
The Answer
Oh my goodness, Grace—twins!! You are a hero for striding across the earth with two whole babies in your stomach. I’m glad to hear you followed that pelvic-floor-testing experience with core and pelvic floor rehab work, too.
A few months ago, I wrote a piece for Wired all about my experience of dealing with my own pelvic floor, which worked just fine all my life and through pregnancy, only to suddenly start causing me unbearable pain anytime I sat down about four months postpartum. I felt like I’d heard about every possible pelvic floor function and malfunction up until that point, and also like I’d done everything I possibly could for my own pelvic floor health, only for it to rudely rise up and try to fight me from within. (I’m enclosing the PDF of the Wired piece, at the bottom of this piece; it’s a good complement to this answer.)
Pelvic floors are still somewhat of a mystery, even to our foremost pelvic floor experts. As late as the '70s, medical professionals had surprisingly little idea of how they worked, or even that it was possible to consciously control the pelvic floor—as far as I was able to gather in reporting that piece, everyone just thought the pelvic floor was just sort of there (until a woman gave birth, at which point it became far less “there,” as best they could tell).
These days, we have a much better grasp of its role in our bodies and how it works, even as everyone draws the pelvic floor wrong in all the medical diagrams. Yes, really. I insisted on getting a correct one for this Wired piece, and now it might be the only anatomically correct diagram on Beyoncé’s internet. It doesn’t help that we can’t even really observe these body parts—the best we can do is literally have a doctor look directly at the area between your legs while they tell you to pretend you are trying to hold in a pee. But pelvic floors sit at the very center of our bodies, and are connected to all the important parts (spine, pelvis, hips). They are not just a ceremonial muscular curtain through which babies sometimes pass. They are involved in basically everything we do, everything we think, everything we feel.