Today we're going to be discussing stress fractures - one of the more serious running injuries, but also one that isn’t particularly well understood by a lot of runners. Therefore, we'll go back to basics - what is a stress fracture, what's happening in the body, and who's more like to get one. We’ll also cover where stress fractures might commonly happen, and then, importantly, we'll also look at what you can do at home to minimise the risks.
What is a stress fracture?
A stress fracture is a small crack in the bone. It’s a type of accumulation injury - one which builds up gradually over time, as opposed to a traumatic fracture which happens suddenly, for example from falling off a bicycle.
When we run, we're constantly putting the skeleton under stress. Generally, that's a good thing - it causes microscopic trauma to the bone, and then when we rest, the body repairs itself and gets stronger in the process.
However, there’s a fine line between running that strengthens the skeleton and running that causes stress fractures.
Where do stress fractures occur?
Stress fractures are very common in runners, due to the repetitive nature of the exercise and the constant stress on the body. Stress fractures in runners occur pretty much anywhere in the lower body. In the clinic, I often see them in areas such as:
Feet;
Shins;
Femur;
Tibia;
Hip;
Sacrum (at the bottom of the spine, just above the tail bone).
The most common stress fractures in runners occur in the feet, lower legs, and hips.
Symptoms of a stress fracture
So, how do you know if you’ve got a stress fracture? There are a number of different symptoms of a stress fracture, including:
A deep aching, burning pain, which gets worse with running or exercise;
A pain that subsides when you stop running;
Bruising;
Swelling;
Pain and tenderness at the point of fracture.
It’s impossible to diagnose a stress fracture without either an x-ray or an MRI scan. If you have any worries that you might have a stress fracture, it’s important that you see a doctor as soon as possible. An untreated stress fracture can often get worse over time, particularly if you continue to run on it.
Why do stress fractures happen?
One of the main reasons I see stress fractures in my clinic is because the bones aren’t strong or dense enough, meaning they cannot cope with the stress of running or exercise, Bone density can be affected by a number of factors, including pre-existing conditions, smoking, obesity, and gender.
I also see a lot of patients with a relatively normal bone density, but who still experience stress fractures from running. A common reason for stress fractures, in this case, is not giving the skeleton enough time to adapt to an increased weekly mileage. This is particularly true of runners who cover more than 60 miles a week, as this puts a huge strain on the weight-bearing bones in the lower body.
Although running is a great activity for strengthening the skeleton, there is a limit. If you’re running anywhere above 40 miles a week, you’re at risk of putting the bones in your lower body under a dangerous amount of stress.
Ignoring other painful conditions, such as shin splints, can also result in a stress fracture further down the line - meaning it’s important to always listen to your body.
How to prevent stress fractures
Whatever kind of distance you run, it’s vital to complement this with other kinds of exercise. Research shows that strengthening work is a really effective way to increase bone density.
Plenty of runners are a bit afraid of strength training - they think it’s going to give them huge muscles, which will slow them down. This is a myth! With strength training, you’ll increase muscle tone just slightly - this will allow these muscles to absorb some of the impact and take the pressure off of the bones.
Research published in the Journal of Sports Medicine suggests that endurance runners who incorporate strength training into their exercise regimes are able to significantly improve their running performance.
Exercises to help prevent stress fractures
Squats and deadlifts are some of the most simple strength exercises to complement your running and to reduce the risk of stress fractures in the feet and legs. If you’re new to strength training, it’s important to see a good PT, to begin with - this will help you to lift the right amount of weight and with the correct form.
When squatting, try and lower yourself down to a 90-degree angle, before pushing through your feet and coming back to your standing position. I repeat this for three sets of twelve reps.
The premise is similar with deadlifts - check with a personal trainer first to make sure you are lifting correctly and not doing anything that could give yourself an injury. In a deadlift, you should feel your hamstrings working as you lean down with the weight. Again, you can do these for three sets of twelve reps.
Summary: how to prevent stress fractures
Stress fractures are tiny cracks in the bone caused by repeated stress during activities like running. To prevent stress fractures in feet, shins, and legs, you can:
Keep a sensible training regime - don’t go from 0 miles to 60 miles in one jump. If you’re planning on running longer distances, increase your weekly distance gradually.
Do strengthening exercises that are going to complement your running. Exercises such as squats and deadlifts can improve bone density and reduce the strain on your bones when running.
If you suspect you might have a stress fracture, don’t keep running on it! See a doctor, who can recommend a proper treatment plan. A medically-qualified osteopath can also help with your recovery process.
Sources
Hong, A., & Kim, S. (2018). Effects of Resistance Exercise on Bone Health. Endocrinology And Metabolism, 33(4), 435. doi: 10.3803/enm.2018.33.4.435
Taipale, R., Mikkola, J., Nummela, A., Vesterinen, V., Capostagno, B., & Walker, S. et al. (2010). Strength Training in Endurance Runners. International Journal Of Sports Medicine, 31(07), 468-476. doi: 10.1055/s-0029-1243639