Deep Core: Your Inner Support System
How Deep Core Muscles Regulate Pressure and Protect Your Health
When we talk about the "core" in Pilates, we’re not just talking about abs. The deep core muscles—your diaphragm, pelvic floor, transversus abdominis, and multifidus—form a kind of internal support system that goes far beyond helping you hold a plank. These muscles work together to regulate something essential to your health and performance: intra-torso pressure, sometimes referred to as intra-abdominal pressure or IAP.
What Is Intra-Torso Pressure?
This internal pressure system plays a central role in your ability to lift, stabilize, breathe, and even regulate your emotional and physiological responses. It changes constantly in response to movement, breath, posture, stress, and even your emotional state. When it’s well-managed, this pressure supports both movement and stillness. When it’s not, the effects can ripple out to cause instability, discomfort, or even injury.
The deep core isn’t made up of just one muscle—it’s a team. The transversus abdominis acts like a corset wrapping around your midsection. The pelvic floor forms the supportive base of this internal cylinder. The diaphragm, your main breathing muscle, sits like a dome at the top beneath your lungs. And the multifidus runs along the spine, providing subtle, segmental support. These muscles don’t simply contract on demand—they coordinate and respond to each other in a dynamic system of give and take.
The Deep Core: More Than Just Muscles
When you inhale, the diaphragm moves downward, which increases intra-torso pressure. To accommodate this shift, the pelvic floor and abdominal wall must respond by eccentrically lengthening. On the exhale, the pressure reduces, and the system resets. This fluid interplay is what allows you to stay both stable and mobile, strong and supple, grounded and responsive.
During exercise, especially in Pilates, managing this pressure becomes even more critical. Whether you’re lifting, balancing, or transitioning between movements, your body is constantly adjusting to create a stable base of support. This system protects the spine, helps you breathe efficiently under load, and allows you to generate force without straining. When deep core coordination is lacking, other muscles jump in to compensate. You might start gripping with the hip flexors, bracing with the upper abdominals, or holding your breath—none of which are sustainable strategies.
Pilates stands apart in how it trains these muscles. Rather than teaching you to brace or bear down, Pilates encourages just the right amount of engagement—training your deep core to activate reflexively, intelligently, and in proportion to the task at hand. This balance is what keeps your body adaptable and resilient.
Breath, Pressure & the Nervous System
Breathing is a vital part of this equation. How you breathe directly affects how you manage intra-torso pressure—and vice versa. Shallow chest breathing, breath-holding, or pushing the belly out can disrupt the delicate pressure system and lead to feelings of tension or anxiety. In contrast, coordinated breath—where the diaphragm, pelvic floor, and abdominal wall work together—activates the parasympathetic nervous system, helping to down-regulate stress, stabilize blood pressure, and bring your body into a more centered state.
This is why Pilates often feels calming and grounding, even while challenging. It supports the nervous system as much as the muscular system, and that dual benefit is especially powerful in today’s overstimulated world.
When you understand how your deep core works to regulate pressure, it becomes clear that this system isn’t just about strength—it’s about integration. It affects how you move, how you breathe, how you feel, and how you respond to the world around you. At SOMA, we teach you to move from this center—not by locking down your core, but by learning to breathe, engage, and adapt with intention.
The result? A body that doesn’t just look strong—but feels strong, supported, and at ease. Because real strength starts at your center. And from there, anything is possible.