You've probably been told to "engage your core." But what does that actually mean? And why do so many people with a strong-looking core still have back pain, instability, or have issues with their pelvic floor?

Think of Your Core as a Can

Here's a helpful image: your core is like a pressurized soda can. The top of the can is your diaphragm. The bottom is your pelvic floor. The sides are your deep abdominal and back muscles.

When all four walls of that "can" work together, your spine is stable, pressure is managed, and force transfers efficiently through your body. When one wall isn't doing its job, the pressure has to go somewhere — and that usually means back pain, pelvic floor symptoms, or reduced performance.

The Diaphragm and Pelvic Floor Are Connected

When you inhale, your diaphragm drops and your pelvic floor gently descends. When you exhale, they both rise. This is a coordinated system — and when disrupted by chronic tension, muscle incoordination, or habits like chest breathing or breath-holding during exercise — the whole system can get out of sync. Research by Hodges and Gandevia (2000) in the Journal of Applied Physiology confirmed this coordinated relationship between the diaphragm and pelvic floor.

Takeaway: Your core is a pressure system — training it means training all four walls to work together, not just your abs.

Why Crunches Miss the Point

Here's a twist most people don't realize - traditional abs exercises like crunches mainly just work the surface-level muscles on the front of your abdomen. They do very little for the deep stabilizing system described above. Worse, if you hold your breath during crunches — which most people do — you're repeatedly spiking downward pressure into your pelvic floor or putting stress in any weakened areas of your core.

For people managing a back injury, hernias, or pelvic floor concerns, this can actually make things worse.

Three Better Places to Start

Here are three evidence-informed approaches to building a truly functional core:

1. Learn to breathe into your ribcage. On inhale, practice letting your ribs expand outward to the sides — not just your belly or chest. This activates the diaphragm properly and sets up the system.
2. Try the dead bug exercise with breath. Lie on your back, arms and legs in the air. As you lower one arm and the opposite leg, exhale steadily. Let the breath guide the abdominal engagement rather than forcefully bracing or sucking your stomach in.
3. Do loaded carries. Farmer's carries (weight in both hands) and suitcase carries (weight in one hand) are some of the best core exercises in existence. They train your whole system to work together under real-world load — while you keep breathing normally.

Bottom Line

If you have lingering issues with back pain, leaking, or back instability, get it checked out. Just doing core exercise won't necessarily solve the problem, it's worth evaluating your core as a system to identify the true cause. Let's take a look at adaptwichita.com.

Sources

Hodges, P. W., & Gandevia, S. C. (2000). Changes in intra-abdominal pressure during postural and respiratory activation of the human diaphragm. Journal of Applied Physiology, 89(3), 967–976.

Smith, M. D., Russell, A., & Hodges, P. W. (2021). Disorders of breathing and continence have a stronger association with back pain than obesity and physical activity. Australian Journal of Physiotherapy.

Lee, D. G., Hodges, P. W., et al. (2019). The role of the abdominal wall and pressure regulation in lumbopelvic function. Journal of Orthopaedic & Sports Physical Therapy.

Bø, K., & Frawley, H. C. (2021). Evidence-based physical therapy for the pelvic floor and core muscle system. British Journal of Sports Medicine.

Grimes, W. R., & Stratton, M. T. (2023). Breathing mechanics, intra-abdominal pressure, and core function during exercise: implications for rehabilitation and performance. Sports Medicine.