In this excerpt from her groundbreaking book on pelvic floor health and sports, Dr. Rachel Selman, DPT, and the NSCA’s 2026 Personal Trainer of the Year, shows how the pelvic floor is the foundation for core strength, a key attribute we all need for endurance and healthy movement patterns in all sports. Let’s explore how the pelvic floor is the foundation of core strength.
The diaphragm, multifidus, transverse abdominis, and pelvic floor work together to coordinate efficient movement patterns. When these “deep core” muscles work well, they give you the freedom to generate force both higher and lower in the body. To meet the demands of everyday life the pelvis has to regulate and disperse a variety of forces:
If the core, which includes the pelvic floor, is unable to accept and appropriately distribute any of these forces, the resulting compensations will assumedly affect athletic performance.
Introducing Your Deep Core
It may be the case that you haven’t been taught anything about your deep core until now—after all, many providers and coaches have lacked information to communicate how to address this issue. Even after seven years of school and a decade of treating athletes, I rarely come across an individual with a solid understanding of how to train the full core, much less knowledge of how that training translates from the treatment table to the field.
The deep core functions like a piston to regulate intraabdominal pressure (IAP). It’s continually monitoring for extremes—moments when there is too much pressure or not enough pressure in play—and determining what can be done when either of those extremes is reached. In short, this is the pressure your body is able to create within the abdominal cavity via selective manipulation of the muscles surrounding it. When your system is “braced” well, it supports the spine by creating a stiff and supportive column around the spine itself.
Your Deep Core Is Like a Canister
You can visualize this system as a soda can—at the top of the can is the diaphragm, at the bottom is your pelvic floor, in front is your transverse abdominis, and in back is your multifidus.
To illustrate the power of stability, let’s say I take an unopened can of soda and set it on the floor. I could place a 45-pound weight on top of it, even add pressure with my foot or squeeze it from the sides, and there will be very little “give.” The can will tolerate significant load and remain resilient. Even if you were to create small dents, they would likely resolve themselves via internal pressure regulation.
The Core Canister Regulates Pressure
This core canister system is pretty amazing, subconsciously working to maintain equilibrium while we sprint, squat, and deadlift. In contrast, consider what would happen if we had a soda can with a thinner wall on one side. Depending on where the can is compromised, pressure will leak when force is applied to the can.
While the visual that follows is intentionally oversimplified, let’s consider the possible effects in the context of your deep core.
A “leak” in any of the areas of your core canister will also require additional compensation around your pelvis, which over time can manifest as musculoskeletal pain.
Coincidentally, this pain is typically treated without any consideration of the pelvic floor.
If your hip labral tear came about due to an inability to regulate force through the pelvic floor and we treat only the hip, we’ve treated the victim without addressing the culprit—which only sets you up for a repeat of the same situation.
The fact that your deep core tends to work at the level below conscious engagement can make it difficult to address dysfunction. After all, it’s hard to “connect” a group of muscles you’ve never really thought about, let alone targeted.
This is why I encourage you to proactively work toward a better understanding of how your body works so that when something does go “wrong,” you are already moving one step in the right direction.
Let’s floor it! See more from Dr. Rachel Selman and her groundbreaking book on pelvic health and sports.
About Floor It
Floor It is the groundbreaking guide to your pelvic floor, the unsung hero of core strength and your hidden powerhouse for sports.
Dr. Rachel Selman, DPT, the NSCA’s 2026 Personal Trainer of the year, offers a fascinating resource to understand pelvic floor dysfunction and pelvic muscle training for endurance sports, team sports, power sports, and sports that involve twisting like tennis and golf.