Jake Smith Bone Stress Injuries in Runners: Why They Happen and What to Do About Them
July 13thIf you’ve ever had a running injury that seemed to come out of nowhere—despite doing all the “right things”—a bone stress injury or stress fracture might be part of the picture.
For many runners, the story sounds familiar.
Training is going well. You’re building fitness, chasing a new goal, or simply enjoying consistent weeks of running. Then a small ache appears. It might feel manageable at first. You push through a few sessions, expecting it to settle.
Instead, it gets worse.
Eventually, walking hurts. Running becomes impossible. Suddenly, you’re facing weeks—or months—away from the sport you love.
Bone stress injuries are one of the most frustrating running injuries we see in the clinic because they often develop gradually and can affect highly motivated people who are doing their best to stay healthy.
The good news? They are rarely caused by a single factor. Understanding why they occur is the first step towards preventing them and recovering well.
What Is a Bone Stress Injury?
Our bones are living tissue.
Every day, your body is breaking down old bone and rebuilding new bone. This process is called bone remodelling and it allows your skeleton to adapt to the demands you place on it. When training loads are appropriate, bone repair keeps up with bone breakdown. When breakdown starts occurring faster than repair, the bone becomes vulnerable.
This is where bone stress injuries develop.
Rather than appearing suddenly like a traumatic fracture, bone stress injuries or stress fractures exist on a continuum. They begin with subtle changes within the bone and can progress to a complete fracture if the underlying issue is not addressed.
Why Do Bone Stress Injuries Or Stress Fractures Happen With Runners?
Most people assume bone stress injuries are simply caused by running too much.
The reality is more complex.
At Kinematics, our physio for runners assessment views bone stress injuries through two key lenses:
1. Biomechanical Factors
These are the physical stresses being placed on your body.
Common contributors include:
- Increases in running volume, speed, frequency or terrain
- Footwear changes
While training load matters, it’s not just about how much running you’re doing. It’s about whether your body has the capacity to adapt to that load.
2. Biological Factors
This is the piece that often gets missed.
Your bones need the right environment to repair and strengthen.
Factors that influence bone health include:
- Energy availability (whether you’re eating enough to support training)
- Calcium and Vitamin D levels
- Bone density
- Hormonal health
- Sleep quality
- Stress levels
- Genetics
Two runners can complete the exact same training programme and have completely different outcomes because their biological capacity to recover is different.
The Part Most Runners Don’t Realise: Muscles Load Bones Too
When people think about bone stress injuries, they often focus on impact.
The assumption is that the ground is the problem.
In reality, bones experience loading from two sources:
- External forces (ground reaction forces when you land)
- Internal forces (muscles contracting and pulling on bone to absorb your landing and to help you propel forwards)
The forces generated by your muscles are much greater than the forces coming from the ground.
This helps explain why certain bone stress injuries occur in specific locations.
Current research by Dorn et al (2012) shows that the calf works the hardest out of all muscles during running speeds up to 7 metres per second. During running, the calf is subjected to significant tensile and compressive forces through the shin. This is why the posteromedial (inside and rearward part) tibia bone stress injury is the most common bone stress injury our physiotherapists see in runners here at Kinematics.
This is why simply blaming “high impact” is often an oversimplification.
The Questions Our Physiotherapist for Runners Ask in a Bone Stress Injury Assessment
A thorough assessment goes far beyond identifying where it hurts.
We want to understand why the injury occurred.
That means exploring:
- Training History (your recent running loads)
- Previous Running-Related Injury History (the injuries you have had in the past)
- Medical History (current medical conditions, hormonal health, previous blood test results, bone density scores)
- Recovery (sleep quality, stress levels, nutrition)
At Kinematics, we don’t view bone stress injuries as isolated bone problems. They’re often the result of multiple factors interacting together. That’s why our running assessment looks at the whole picture. Elite care for the everyday runner means understanding not just where the injury is, but why it happened in the first place.
What To Do If You Suspect a Bone Stress Injury
If you have pain that:
- Has become increasingly localised
- Worsens with harder running efforts
- Is affecting your ability to walk or train
- normally increases at night
It’s worth getting assessed early.
The sooner the contributing factors are identified, the sooner you can begin addressing them and creating a plan for recovery.
Ready to Get Back to Running With Confidence? Our Physio for Runners Are Here To Help
If you have been dealing with a persistent niggle that you now think sounds a lot like a bone stress injury, a comprehensive running physio assessment in Melbourne can help identify what’s driving the problem and map out your next steps.
At Kinematics, our running-related injuries physio combines hands-on assessment, rehabilitation planning, and a whole-person approach to help you understand what’s happening and build a pathway back to doing what you love.