From Ozempic to Ouch: What’s Causing That Back Pain?

There’s no denying it, weight loss injections like Ozempic and other GLP-1 receptor agonists are everywhere right now. Developed initially to manage type 2 diabetes, these medications are now being prescribed (and in some cases self-sourced) to help people lose significant amounts of weight, and quickly.

You’ve probably seen the headlines, heard the celebrity endorsements, or had a friend proudly say they’ve finally dropped the weight that wouldn’t budge.

But here in the clinic, we’re starting to see the other side of the story. More clients are presenting with:

• Lower back pain,

• Hip and knee discomfort,

• Neck and shoulder issues,

• Or simply a feeling of being “weaker” and “less stable”.

These complaints often come from people who’ve lost a lot of weight fast, particularly without a structured strength plan alongside their nutrition or medication strategy. What’s going on in the body?

Here’s the science, simplified:

1. You’re losing more than just fat:

GLP-1 medications often reduce appetite so effectively that people unintentionally under-eat protein and calories. Without enough stimulus or nutrition, your body doesn’t just burn fat, it also breaks down muscle tissue.

Research shows that up to 30–40% of weight lost on GLP-1 drugs can come from lean body mass (i.e., muscle), not just fat.

When you lose muscle mass, particularly the deep stabilising muscles that support your spine, hips, and pelvis, your joints and ligaments have to absorb more load and impact. That’s a recipe for pain or overuse injuries.

2. Postural changes are inevitable:

Weight loss can alter your centre of gravity, especially if it happens quickly. The curves of your spine, the tilt of your pelvis, and the angles at your knees and ankles may all adjust, often subtly, but enough to strain areas that previously felt fine.

Without tailored movement retraining, these shifts can result in:

• Overworked back muscles,

• Core instability,

• Poor coordination or balance reactions.

3. Reduced fat cushioning = Less shock absorption:

Fat around joints, especially the lower back and hips, does more than store energy; it also provides passive padding and shock absorption. When that’s lost quickly, and you’re not moving efficiently, joint surfaces and tendons may take more of a hit with every step, bend, or twist.

“But I feel fitter – Why am I in more pain?”…

It’s a fair question, and one we often hear. People are understandably surprised to be lighter on the scale but heavier with pain or tension.

Here’s why:
Fat loss doesn’t automatically mean functional fitness. If you’re losing muscle faster than you’re gaining control or strength, you’re essentially removing the body’s internal support system. It’s like pulling out scaffolding before the building has stabilised.

Even simple movements, like walking uphill, sitting upright at a desk, or lifting a bag, now demand more from tissues that aren’t conditioned for it.

How Free Your Body Therapy can help:

We’re not here to tell anyone how to approach their weight journey. Whether it’s medically supervised, self-managed, or completely unrelated to GLP-1s, we meet you where you’re at.

But we do care deeply about how your body moves, feels, and functions. And that’s where we come in.

1. Detailed Physio & Osteo assessments: We look at your posture, movement control, joint load, and muscular support, especially around the spine, hips, and core.
2. Progressive strength-based rehab: Using a Pilates-informed approach alongside targeted resistance work, we help you regain strength where it counts, especially in those deep stabilising systems often missed by general exercise.
3. Restore & rebuild function safely: Our team supports you as your body adapts. Whether you’re newly mobile after weight loss or struggling with pain, we tailor your care so your mobility matches your new body, not your old one.

Final Thoughts: Weight may drop fast, but stability takes time.

If you’ve lost weight recently,  whether through medication, lifestyle change, or illness, your musculoskeletal system might be trying to keep up. Don’t ignore new aches, weird stiffness, or a sense that your body feels unfamiliar.

Instead, could you give it the support it deserves?

FYB Team x