Your Low Back Pain Isn't From Playing Too Hard — It's From Sitting Too Long
By Dr. Matt Heisig, DC | Athlete Lab Performance Chiropractic | Long Beach, CA
You played some beach sports, lifted weights or went for a run over the weekend. Hours in the sand cutting hard, time on the gym floor lifting heavy, or some miles out on the strand stride after stride. You felt great doing it.
Monday morning you can barely get out of bed.
Your low back is locked up, your hips feel like they're made of concrete, and you're walking like you aged twenty years overnight. You tell yourself you'll stretch more next time. Maybe warm up better. Maybe take it easier.
But the same thing happens the following weekend. And the weekend after that.
This isn't bad luck. It isn't age. And it isn't because you played too hard. It's a structural pattern that starts Monday through Friday — and doesn't get addressed until it's too late.
The Real Problem Starts at Your Desk
Here's what's actually happening: most people spend forty-plus hours a week sitting. Sitting at a desk job, sitting when you hit the couch after work, heck, even sitting on the toilet scrolling Instagram a little too long. Sitting shortens your hip flexors — specifically the psoas and iliacus, a muscle group that attaches from your lumbar spine through your pelvis to your femur. These muscles help bring your thigh toward your torso. When these muscles stay in a shortened position for hours at a time, five days a week, they stop lengthening the way they're designed to.
By Friday afternoon, your hip flexors are essentially stuck in a shortened state. Your pelvis has tilted forward into anterior pelvic tilt. Your lumbar spine gets pulled into extension. And your glutes — which are supposed to be the primary movers in running, cutting, and jumping — have been neurologically inhibited by the shortened hip flexors pulling from the front.
Then the weekend arrives and you spend a couple hours sprinting out onto a beach for your sports, hit the strand for that run, or go pump some weights in the gym.
The research backs this up. A cohort study of ice hockey players found that athletes with hip flexor tightness were more than three times more likely to develop low back pain than those with normal hip flexibility — missing significantly more games and practices as a result. While this research focused on hockey players, the mechanism is identical regardless of your sport — hip flexor tightness creates measurable increased risk of low back pain whether you're on the ice, the sand, or the gym floor.
The problem isn't those few hours. The problem is the forty hours that came before it.
What Anterior Pelvic Tilt Actually Does to Your Low Back
Anterior pelvic tilt — where the front of your pelvis drops and your low back arches excessively — changes everything about how your spine loads under movement. When your pelvis is in this position:
Your lumbar vertebrae compress into extension with every running stride
Your glutes can't fully activate because their mechanical leverage is compromised
Your hip flexors do even more work than they should — perpetuating the cycle
Your core can't stabilize properly because the foundation it sits on is tilted
Every sprint, every lateral cut, every deadlift, every mile happens on top of this already compromised foundation. The low back isn't the weak link — it's the structure absorbing the load that should be distributed across your entire posterior chain.
By Sunday evening the muscles around your lumbar spine are exhausted from compensating for a pattern that was set up days before you even stepped foot on the sand, the strand, or the gym floor.
Why Sand Makes It Worse — For Beach Sport Athletes
Playing on sand creates significantly higher demands on your hip extensors and stabilizers than playing on grass or hardwood. Every stride requires more force to push off. Every cut requires more stability to control. Every landing requires more absorption through the lower extremity chain.
For a posterior chain that's already inhibited and a pelvis already in anterior tilt — sand is the worst possible surface to throw that much load at. Your low back ends up doing work your glutes and hips were supposed to do.
The PRI Lens — What Nobody Else Is Looking At
In the PRI world, we don't just look at the low back in isolation. We look at the whole pattern — how your pelvis, ribcage, and diaphragm relate to each other and how asymmetry in that system drives uneven loading through your spine.
Most people with chronic low back pain after long work weeks and heavy weekend activity have a Left AIC (Left Anterior Interior Chain) pattern — a predictable neurological asymmetry where the left hip flexors and right low back extensors are overworked while the right glutes and left posterior chain are underutilized. This isn't a weakness problem. It's a neurological pattern that doesn't resolve with stretching alone.
This is why two athletes can have the same job, play the same sport, and train the same hours — but one gets low back pain after every weekend and the other doesn't. The one who doesn't has a more balanced neurological pattern driving their movement. The one who does has an asymmetry nobody has identified or addressed.
Quick Self-Check: Is Your Low Back Set Up to Fail?
Stand in front of a mirror barefoot.
Does one hip sit higher than the other?
Does one foot turn out more than the other at rest?
When you put your hands on your hips, does one side feel more forward than the other?
Does your low back feel compressed or tight when you stand up straight?
If yes to any of these — your pelvis is already in a pattern that's loading your low back asymmetrically. Every sprint, cut, deadlift, and mile is happening on top of that.
What Actually Fixes It
Three things that most treatment protocols either skip or rush through:
1. Release the overworked tissue. Deep soft tissue work to address the psoas, TFL, lumbar paraspinals, and other muscles that have been chronically overworked. This isn't a foam roll — this is targeted manual therapy to the specific structures that are driving the pattern.
2. Reposition the pelvis. PRI-based repositioning exercises that restore the neurological balance between your hip flexors and posterior chain. The goal isn't just stretching the hip flexors — it's restoring the relationship between your pelvis, ribcage, and diaphragm so the pattern doesn't immediately return.
3. Activate the right muscles. Once the pelvis is in a better position, your glutes and posterior chain need to be activated in that new position. This is the piece most people skip — and why stretching alone never seems to hold. If you don't activate the muscles that are supposed to be working, the overactive ones just take over again.
The Pattern That Changes Everything
The athletes who stop getting low back pain after every weekend aren't the ones who stretched more or warmed up longer. They're the ones who addressed the underlying pattern — the anterior pelvic tilt, the neurological asymmetry, the inhibited posterior chain — and gave their low back a foundation it could actually work from.
You shouldn't have to choose between your career and your weekend activities. You shouldn't have to spend Monday limping around the office paying for a weekend you loved.
Come see me at Athlete Lab before that pattern gets any deeper.
Dealing with chronic low back pain or hip tightness after weekend activity? Book your Initial Evaluation at Athlete Lab Performance Chiropractic in Long Beach. No referral needed — just show up ready to move.
McHugh MP, Tyler TF, Schmitt BM, Kwiecien SY, Nicholas SJ. "The Association Between Hip Flexibility and Low Back Pain in Ice Hockey Players." Orthopaedic Journal of Sports Medicine. 2025. PMID: 41660292. DOI: 10.1177/23259671251404068
About the Author: Dr. Matt Heisig is a Doctor of Chiropractic and founder of Athlete Lab Performance Chiropractic in Long Beach, CA. A graduate of Southern California University of Health Sciences with a sports medicine emphasis, Dr. Matt utilizes PRI methodology, active movement rehab, and performance-focused care for athletes at all levels. He sees patients at Long Beach Rising on weekends.
Athlete Lab Performance Chiropractic is located inside Long Beach Rising at 205 E Anaheim St, Long Beach, CA 90813. Dr. Matt Heisig, DC sees patients on weekends and accepts HSA/FSA.