Understanding Running Injuries: Why They Happen and Where They Show Up

 

Running places repetitive mechanical load through the same tissues, often thousands of times per session. Because of this, running injuries tend to follow predictable patterns and are usually linked to how training load is applied and managed over time, rather than a single incident.

For many runners searching for answers around “why do running injuries happen” or “how to prevent running injuries”, the key lies in understanding how your body adapts to load.

What are the Most Common Running Injuries?

While injuries can occur anywhere, certain areas tend to take the brunt of repetitive load.

Injury patterns in runners shift with age, largely due to differences in tissue capacity and how the body responds to load.

Younger runners are more likely to present with knee pain from running, such as patellofemoral pain or iliotibial band syndrome, as well as bone stress injuries (most commonly in the tibia). This is partly because their muscles and tendons tend to tolerate load well, allowing them to generate higher forces more efficiently, which can shift stress toward bone. As bone adapts more slowly than muscle, it is often the limiting factor (Lopes, AD., et al. 2012). 

In contrast, Masters runners are more likely to experience soft tissue running injuries, including issues involving the Achilles tendon, hamstrings, calves, and gluteal tendons. With age, tendon elasticity and recovery capacity decrease, and overall tissue repair becomes slower. When combined with years of accumulated training load, this increases the likelihood of soft tissue structures becoming overloaded (Lopes, AD., et al. 2012). 

Why Do Running Injuries Actually Happen?

Most running injuries come back to a simple concept: too much, too soon.

In clinical terms, this is called a load mismatch, where the demands of training exceed what your tissues are currently prepared to handle.

The challenge with running is that it’s inherently repetitive. Each step is a near-identical movement, so even a small gap between load and capacity can build quickly over time.

Under the surface, a few key things are happening.

Running is efficient because it’s repetitive, but that same repetition means the same tissues are repeatedly exposed to stress. The body is very capable of adapting to this, but only when it’s given enough time and variation in training.

When every run starts to look the same – same pace, same distance, same terrain – those positive adaptations begin to plateau.

At that point, instead of getting stronger, tissues can start to fall behind. Small amounts of micro-damage occur with every run (which is normal), but if the rate of damage exceeds the body’s ability to repair, that’s when problems start to develop.

What often catches runners out is that symptoms don’t appear straight away.

There’s usually a delay.

It’s common for injuries to surface 3-6 weeks after the actual training error or period of increased stress.

So the niggle you’re feeling now likely didn’t start this week – it’s been building in the background for some time.

Understanding Load: It’s More Than Just Kilometres

When most runners think about training load, they focus on what they can measure. This is known as external load, and it typically includes:

• Distance (km)
• Intensity (speed, hills)
• Frequency

These metrics are important and form the basis of most running programs, but they only tell part of the story.

What often gets overlooked is internal load – how your body responds to that training.

Two runners can complete the same session on paper, but experience very different levels of stress depending on what else is going on in the background.

Common factors that increase internal load include:

• Poor sleep
• High life stress
• Inadequate nutrition
• Fatigue
• Illness

When these factors are present, the same run becomes a much greater physiological challenge.

What looks like a manageable session externally may actually be pushing the body closer to its limit. 

Research is increasingly showing that training load is more than just weekly distance and should also consider how the body is responding to that load internally. As mentioned in the Journal of Orthopaedic & Sports Physical Therapy article titled “Moving Beyond Weekly “Distance”: Optimizing Quantification of Training Load in Runners” by Max Paquette, Christopher Napier, Richard Willy and Trent Stellingwerff. https://www.jospt.org/doi/epdf/10.2519/jospt.2020.9533

Why This Matters for Injury Prevention?

Understanding the relationship between load, recovery, and tissue capacity is the foundation of effective running injury prevention. It’s not just about how much you run overall – it’s about how quickly your load changes, and how each session compares to what your body is prepared for.

Once you’ve had a running-related injury, your likelihood of another injury increases (Joachim, M. R et al., 2024). Once the body has been injured, it can remain more vulnerable if the underlying contributors haven’t been addressed. That may include strength deficits, poor load progression, recovery issues, movement strategies, or returning to training before true capacity has been rebuilt.  

General recommendations from Sports Medicine Australia emphasise the importance of proper warm-ups, strength training, and allowing adequate recovery. See more: https://sma.org.au/ 

When Should You Seek Physiotherapy for a Running Injury?

If you’re experiencing:

• Pain that persists during or after running
• A niggle that hasn’t improved within 1-2 weeks
• Recurrent injuries in the same area
• A noticeable drop in performance

It’s worth having this assessed early.

Early intervention allows us to:

• Identify the true driver of the injury
• Adjust training load appropriately
• Build strength and capacity in the right areas
• Prevent progression into more complex or long-term injuries

CTA: Take Control of Your Running Injuries

If you’re dealing with a running injury or want to prevent one before it starts, our physiotherapy team can help you understand exactly what’s going on – and what to do next.

At Malvern Physiotherapy Clinic, we don’t just treat symptoms. We assess your training load, movement patterns, strength, and recovery capacity to create a clear, personalised plan.

👉 Book a running assessment today with running expert Jacinta Pedis:
https://www.malvernphysio.com.au

About the Author: Jacinta Pedis

Jacinta Pedis is a physiotherapist at Malvern Physiotherapy Clinic with a strong clinical focus on running injuries, post-operative rehabilitation, and chronic musculoskeletal conditions.

She graduated from La Trobe University and has experience working in the public health system at The Alfred Hospital. Jacinta has completed further training in chronic pain and osteoarthritis management, and is currently undertaking her Master’s of Musculoskeletal Physiotherapy.

Jacinta has a particular interest in:

• Running-related injuries (including bone stress injuries and tendon conditions)
• Load management and return-to-running programs
• Strength-based rehabilitation
• Female athlete health, including RED-S and bone health

She combines hands-on treatment, education, and targeted exercise programs, alongside resistance training, to help patients return to running with confidence.

References: 

Lopes, A. D., Hespanhol Jr, L. C., Yeung, S. S., & Costa, L. O. P. (2012). What are the main running-related musculoskeletal injuries? A systematic review. Sports medicine, 42(10), 891-905. 

Joachim, M. R., Kuik, M. L., Krabak, B. J., Kraus, E. M., Rauh, M. J., & Heiderscheit, B. C. (2024). Risk factors for running-related injury in high school and collegiate cross-country runners: a systematic review. Journal of Orthopaedic & Sports Physical Therapy, 54(2), 120-132. 

Published May 20, 2026