Blog 3: Lower Back Pain in Athletes
Part 3: Core Strength and Activation: Why Your Core Is Not What You Think It Is
Welcome back to Lower Back Pain in Athletes. Part 1 covered the types and causes of athletic lower back pain and why the cycle of improvement and relapse is so predictable. Part 2 went deep on the three upstream and downstream drivers, weak glutes, restricted hip mobility, and thoracic stiffness, and how each one forces the lumbar spine to compensate. Part 3 addresses the piece that most athletes think they already have sorted but almost universally do not: the core.
If you have ever done planks and crunches religiously and still dealt with lower back pain, this part is for you.
The Core Is Not a Six-Pack
The most pervasive misunderstanding in athletic training is that core strength means strong superficial abdominal muscles. Sit-ups, crunches, leg raises, exercises that train the rectus abdominis and the visible musculature of the anterior trunk. These muscles have their place. But they are not the core that matters for lower back pain prevention and athletic performance.
The core that protects the lumbar spine is a system of deep muscles that create intra-abdominal pressure, stabilize the spine in neutral, and transfer force efficiently between the upper and lower body. It includes:
The Transverse Abdominis:
The deepest abdominal layer, which wraps around the trunk like a corset and creates the intra-abdominal pressure that stabilizes the lumbar spine before any limb movement begins
The Multifidus:
The deep segmental stabilizer of the lumbar spine that runs directly between vertebrae and controls micro-movement at each spinal level. Research consistently shows that multifidus atrophy and delayed activation are among the most reliable findings in people with lower back pain.
The Diaphragm:
The primary breathing muscle doubles as the roof of the core canister. Proper diaphragmatic breathing is foundational to core pressure and lumbar stability. Breath-holding or chest breathing during exercise compromises the entire system.
The Pelvic Floor:
The base of the core canister. The pelvic floor works in coordination with the transverse abdominis and diaphragm to create the pressure that protects the lumbar spine under load.
These muscles do not create movement. They resist it. And that distinction is everything when it comes to lower back pain in athletes.
The Core's Job in Sport Is Anti-Movement
In sport, the core's primary job is not to flex, rotate, or extend the spine. It is to prevent unwanted movement of the spine while the limbs produce and absorb force. This is what exercise scientists call anti-movement capacity, and it is what is missing in most athletes with lower back pain.
Think about a running stride. The foot contacts the ground and a ground reaction force travels up the leg. The core's job is to stiffen the trunk in that moment; resisting the rotation, lateral flexion, and extension forces that the ground contact creates, so that the force transfers efficiently through the kinetic chain rather than leaking through spinal movement. An athlete with a strong anti-rotation and anti-extension core transfers force cleanly. An athlete without one absorbs it through the lumbar spine instead.
The same principle applies in golf, where the core resists the rotational forces of the swing. In hockey, where it resists the lateral forces of the skating stride. In cycling, where it resists the extension and rotation forces that sustained pedalling creates across the lumbar segments.
Why Standard Core Training Often Fails Athletes With Back Pain
Most gym-based core training emphasizes spinal movement; crunches, sit-ups, Russian twists, and back extensions. These exercises load the very structures that are already irritated in athletes with lower back pain. They train the spine to move under load when the goal should be to train it to resist movement under load.
Research by Dr. Stuart McGill, one of the leading spine biomechanics researchers in the world, consistently demonstrates that spinal flexion under load, the motion of a crunch or sit-up, is among the most reliable mechanisms for disc injury in the lumbar spine. High-repetition spinal flexion training in an athlete who already has disc irritation is not rehabilitation. It is provocation.
What actually works:
Anti-extension work — the plank and its progressions train the core to resist extension forces. The key is maintaining a neutral lumbar spine throughout — not a flat back, not an arched back, but the natural lumbar curve under active muscular control.
Anti-rotation work — the Pallof press and cable chop variations train the core to resist rotational forces. This is the most directly sport-relevant core training available for golfers, hockey players, runners, and any rotational sport athlete.
Anti-lateral flexion work — single-arm farmer carries, suitcase carries, and lateral plank progressions train the core to resist side-bending forces. Essential for runners managing single-leg loading and hockey players stabilizing through the skating stride.
Bracing and intra-abdominal pressure — learning to create and maintain appropriate trunk pressure during loaded movements is foundational. This is the skill that transfers most directly to protecting the lumbar spine during sport.
Activation Before Loading
As we established in our Activate Before You Train series, the deep stabilizing muscles of the core, particularly the transverse abdominis and multifidus, are prone to delayed activation and inhibition in athletes with lower back pain. Research shows that in people without back pain, the transverse abdominis activates before any limb movement. In people with back pain, that pre-activation is significantly delayed or absent.
This means that loading the spine before the deep stabilizers are engaged leaves it unprotected during the most vulnerable phase of movement, the initiation. Teaching athletes to consciously establish trunk pressure and deep core engagement before lifting, running, and training is one of the most important interventions available for lower back pain prevention and rehabilitation.
Up Next: Movement and Mechanics
The core is trained. But if the movement patterns themselves are loading the lumbar spine incorrectly, all the core strength in the world will not fully protect it. Part 4 of Lower Back Pain in Athletes covers the specific movement and mechanics errors I see most in athletes with lower back pain across running, cycling, golf, hockey, and everyday training. See you there.
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Core strength for lower back pain is not about doing more planks. It is about training the right system in the right way. If you want to know exactly what your core is doing under load and where the gaps are, reach out to book an assessment with Dr. Keirstyn at Endurance Therapeutics.
📍 Endurance Therapeutics | Oakville, Ontario
📞 905-288-7161