022 - Low Back Pain & Muscle Activation: Strength Isn’t the Problem
Low Back Pain: It’s Not Always Weakness—It’s Misfire
You can’t strengthen what your brain won’t fire.
A new study reveals that individuals with low back pain (LBP) don’t necessarily have weaker spinal and hip muscles—they just can’t activate them as well. That’s a problem, and it changes how we train.
Key Findings from the Study
Researchers used rehabilitative ultrasound imaging (RUSI) to compare activation of the erector spinae (ES) and gluteus medius (GM) in individuals with and without LBP. Here's what stood out:
LBP patients had significantly lower activation—not due to muscle atrophy, but due to impaired neuromuscular control.
3.46% less activation in the erector spinae, and 1.93% less in the gluteus medius.
No size difference at rest—just a failure to fully contract under demand.
Patients often reported discomfort during contractions, suggesting inhibition and faulty control, not just weakness.
Why This Matters
If your stabilizers don’t fire when needed, your prime movers compensate—and that’s how chronic pain patterns are born.
This isn’t about building bigger muscles. It’s about retraining your system to engage what’s already there—on demand, under load, and without hesitation.
3 Tactical Rehab Strategies
Restore the Signal
Use biofeedback (RUSI or EMG) to train activation.
Start with low-load isometrics—earn the contraction before adding complexity.
Build Smart Stability
Prioritize exercises that reinforce lumbo-pelvic control: single-leg balance, resisted hip abduction, and trunk extensions.
Keep reps crisp and intent-driven—this is neural, not just muscular.
Stop Chasing Strength Alone
Don’t skip past motor control deficits. If ES and GM aren’t turning on, no amount of load fixes the root problem.
Identify and correct compensations before reinforcing dysfunction.
Stay Thick.
Farley JR, Pokhrel S, Koppenhaver SL, Fritz JM. Comparison of erector spinae and gluteus medius muscle thickness and activation in individuals with and without low back pain. J Bodyw Mov Ther. 2024;39:67-72. doi:10.1016/j.jbmt.2024.02.042