I couldn’t tell you how many women and men have been surprised when I tell them they have muscles “down there.” We talk about hamstrings and biceps and abs but nobody talks about the pelvic floor muscles. I get it… it’s a sensitive, private area of our body. But we have to start talking and educate ourselves if we want to understand our bodies and advocate for the care we deserve! So I’m going to go through the basics of the pelvis and how these muscles work in our body. This first blog will be an introduction to the muscles but in future weeks I’ll talk about the other anatomical structures - bones, nerves, ligaments, blood vessels - and how these interact to keep us moving, dry, and pain free.
The pelvic floor is a group of muscles located in the pelvis. These muscles make a sling from the pubis (pubic bone) to the sacrum and coccyx (tailbone) and between the ischial tuberosities (sit bones).
The muscles can be divided into 3 layers:
The deepest layer includes pubococcygeus, iliococcygeus, and coccygeus and are known collectively as the pelvic diaphragm. This layer provides the lift of the pelvic floor to support the bladder, uterus, and bowel. The pelvic diaphragm provides the bottom layer of support for the abdominal and pelvic cavities and helps to regulate pressure within the abdomen. We’ll talk more about this soon and how it relates to Diastasis Rectus Abdominis in new moms.
The middle layer consists of the deep transverse perineal, sphincter urethrovaginalis, compressor urethra, and the external urethral sphincter.
The superficial layer is composed of superficial transverse perineal, bulbocavernosus, ischiocavernosus and the external anal sphincter.
The middle and superficial layers of muscles function as the sphincters for the urethra, vagina, and anus and help us to be continent so that we do not leak urine or feces. They release when we are sitting on the toilet in order to empty the bladder or bowels and during intercourse to allow penetration.
The pelvis is home to organs, blood vessels, nerves, lymph vessels, and lymph nodes. All of these structures are supported by the pelvic floor. Maintaining mobility and strength in the pelvic floor can help keep your pelvis fit and keep you feeling and moving happily.
The pelvic floor muscles work in several aspects of our daily lives. They help us with bladder and bowel function and sexual activity. They are always working, even when we are asleep! The pelvic floor must maintain a baseline of muscle activity to hold in urine and feces and to keep our pelvic organs in an optimal position while we are sitting, standing, and exercising. Of course, we need the muscles to be able to work at different levels, just like we need to be able to pick up a pen or a 30 pound bag of dog food. Both may use our biceps but the bag of dog food requires a greater amount of force. In the same way, while we are sleeping or sitting the pelvic floor muscles work at a much lower level than when we are jumping on a trampoline.
During sexual activity the muscles of the pelvic floor rest or lengthen to allow for penetration and work or contract during an orgasm. For men, the pelvic floor also provides a base to support and maintain an erection.
The pelvic floor also provides stability to the pelvis during activity. It works with the abdominal, hip, and back muscles to provide stability during walking, running, jumping, and core exercises. It’s important that the pelvic diaphragm works only when appropriate and not to compensate for weakness in hip or abdominal muscles. This can lead to pelvic pain or bladder and bowel difficulties.
Keep reading this blog for more information on pelvic floor anatomy and function. Every Thursday I'll break down different structures and delve into how they work, or don’t work, in conditions such as overactive bladder, DRA, and orgasm. Until then follow our Instagram, @thefitpelvis, for daily facts and pelvic health tips.