Why Running Injuries Occur and How to Reduce Your Risk
Running injuries are rarely caused by just one thing. Instead, they usually develop over time because of several factors working together.
When the amount of training or stress placed on your body becomes more than it can handle for too long, a running injury can occur. By understanding what these various factors are and how they lead to problems, we aim to reduce the risk of injury.
To make sense of this, it helps to think in simple terms:
Some things increase the load on your body (for example, how much and how hard you train).
Other things affect your ability to handle that load (for example, sleep, nutrition, stress, and recovery).
Understanding both sides of this equation can go a long way toward helping you stay healthy and running comfortably.
The Simple Injury Equation
You can think about running injury risk like this:
When LOAD is greater than CAPACITY for too long → INJURY
Short episodes of extra training are not always a bad thing. In fact, athletes sometimes increase their training slightly for short periods to encourage the body to adapt and get stronger. However, if you continue pushing and training at high loads, without giving your body enough time to rest and recover, that’s when problems start to appear.
What Affects the LOAD on Your Body
Load refers to how much stress your body experiences from all activities — not just running. Two runners might complete the same training plan but experience very different amounts of load depending on things like sleep, nutrition, and daily life stress.
Common factors that increase load include:
Running distance or duration – How far or how long you run.
Running intensity – How hard you run (pace, effort, or heart rate). More intense running means higher stress.
Hills or elevation – Running uphill or downhill adds extra mechanical strain.
Cross-training – Activities such as cycling or swimming also add to your overall workload.
Strength training – Lifting weights or doing gym work contributes to your total load.
Everyday life – Work, study, childcare and other physical activities can all add up and affect recovery.
Even if your running program stays the same, extra stress from other areas of life and training can still push your total load too high.
What Affects Your CAPACITY to Handle Load
Your capacity is your body’s ability to tolerate and recover from stress. When capacity drops because of fatigue, poor sleep, stress, or illness- even your usual training can start to feel much harder.
Key factors that influence capacity include:
Previous injuries – Past injuries increase the risk of new or recurring problems.
Training background – Runners with more consistent training over time are generally more resilient.
Sleep – Good sleep helps your body recover and adapt. Poor sleep makes you more vulnerable to injury.
Illness – Being unwell temporarily lowers your capacity to train.
Stress and mental health – High stress, anxiety, or low mood can make recovery harder and increase injury risk.
Nutrition – You need enough energy to support both daily life and training. Undereating or skipping meals can lead to fatigue, poor recovery, and injury.
Running technique – Overstriding (landing the foot too far in front of the body) is linked to knee and shin pain.
Biomechanics – How your body moves affects where and how load is distributed through your muscles, bones, and joints.
Strength and endurance – Building muscle strength and power helps protect against common running injuries.
Bone health – Low bone mineral density increases the risk of stress fractures. Getting enough calcium, vitamin D, and doing weight-bearing exercise can help keep bones strong.
Bringing It All Together
To reduce your injury risk, it’s important to pay attention to both sides of the equation — the load you place on your body and your capacity to handle it.
Many runners get injured not because they train too much, but because something else (like poor sleep, low energy, or high stress) has reduced their ability to cope with training.
Practical Tips for Staying Injury-Free
Increase training gradually — small, consistent progress is better than sudden jumps.
Fuel your body properly — make sure you’re eating enough to support training and recovery (if unsure, speak to a dietitian).
Prioritise sleep — aim for quality rest to let your body adapt.
Manage stress — recovery isn’t just physical; mental rest matters too.
Include strength training — a few sessions a week can build resilience and protect against injury.
By finding the right balance between load and recovery, you’ll not only lower your risk of injury but also enjoy your running more and keep progressing safely.
Rachel Jeffrey is known for helping injured runners get back to their best. Rachel is an avid runner herself and is passionate about all things running and preventing running injuries.
Rach has experience treating a range of running related injuries, such as:
running related lower limb tendinopathies
patellofemoral pain and pathology
knee pain and injuries
knee and hip osteoarthritis
hip labral tears and pathology
femoro-acetablular impingement
deep gluteal syndrome
shin splints/medial tibial stress syndrome
bone stress injuries
foot injuries and problems including bursitis, plantar fasciitis, heel pain, foot pain and bone stress
