The #1 Lie About Back Pain:“Rounding Your Back Is Bad”

One of the most common beliefs in fitness and rehab is that any rounding of your spine is dangerous. That idea didn’t come from nowhere. Much of it traces back to lab research by Stuart McGill, where spinal segments (often pig spines) were tested under repeated loading to understand how discs fail. Those studies taught us a lot about spinal mechanics—but they also scared a lot of people into thinking their spine should never move.

Here’s the problem.

Those studies used pig spines, not human spines, which are shaped and loaded differently. They also tested isolated spines—no muscles, nervous system, blood flow, recovery, adaptation, or movement variability. In real life, those systems matter a lot.

This reminds me of the old rule: “Never let your knees go past your toes.” It started as a simple guideline for beginners, but over time it became a hard rule—one that actually limits strength, mobility, and confidence. The same thing has happened with spinal flexion.

In reality, back pain during flexion usually shows up when:

Tissues are loaded beyond their current capacity

The movement is repeated faster than the body can adapt

Flexion is suddenly introduced after years of avoidance

It’s done under fatigue or high stress

Avoiding spinal movement sounds easier than gradually building tolerance—but it often backfires.

No movement is inherently bad. Context, capacity, timing, and progression matter. The goal isn’t to protect your spine from movement—it’s to prepare it for movement.