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Out of all the potential injuries athletes can suffer, stress fractures are among the most common. According to a study published in the journal Sports Health, fractures account for 31 percent of injuries among runners and women are twice as likely as men to fall victim to one.
While no injury is good stress fractures should rank pretty high up on injuries runners want to avoid. It’s a sentence for rest and rehabilitation and can stop you running for months on end.
Podiatrist Priya Parthasarathy finds it to be a daunting injury to work with, specifically when her clients are runners. “My runners usually have the toughest times with restrictions (which include not running for usually six weeks) and sometimes are not compliant with the boot.”
If you’ve never endured this injury, there are definitely some things you should know—including the warning signs and how to prevent it.
What is a Stress Fracture?
Bones are constantly remodeling themselves to remain strong and resilient enough to cope with the stresses applied to them. Stress fractures can occur for two reasons: If a healthy bone is overused. In long distance running where the bones are under more stress than normal, the bone may not be able to repair itself at the rate that it’s being damaged, leading to fractures. The other reason is if a bone is abnormal. That can be the case with something like osteoporosis where the bone can fracture even when under normal strain.
The most common sites for stress fractures are in the shin bone (known as the tibia) and in the bones of the feet (known as the metatarsals). “They tend to take the most stress when running,” says Dr. Parthasarathy of the metatarsals.
Who’s at risk of getting stress fractures?
Stress fractures are common in athletes but there are various factors that can make you more susceptible. Some of these will be environmental, meaning things you inflict on yourself, such as your training routine, while others will be personal to you and may well be out of your control, such as gender and your anatomy.
“Stress fractures are different from a regular fracture because it progressively develops from repetitive force in one area. The bone is unable to adapt to the increase in mechanical load and cannot heal,” says Dr. Parthasarathy .
Certain factors in training have been shown to contribute to a higher risk, such as a high mileage training program, inadequate recovery between sessions, training on fatigued muscles, and running hills, especially down hill. Running on harder surfaces has been shown to increase the risk, too.
“Stress fractures are common in runners that go too fast or far too soon. Increasing mileage, speed, or frequency too quickly may not give your bones enough time to adapt to the increased mechanical load,” she says.
Personal risk factors include being female, poor nutrition (particularly low calcium), and smoking. What’s often referred to as the female athlete triad or RED-S; low bone density, irregular periods, and low BMI, can put female runners at a higher risk of developing stress fractures.
What does a stress fracture feel like?
Stress fractures cause pain in the bone which gradually worsens, presenting earlier in a training session. If it’s not treated, the pain will worsen further and be present in normal day-to-day activities. The area of bone will be tender when it’s touched and there may be swelling and bruising seen too.
When it’s in the foot, you may feel it when walking or running or at the end of the day when you are finally off your feet. It may present as swelling or aching that doesn’t get better after utilizing the RICE method (rest, ice, compression, elevation).
It can be diagnosed by various imaging such as X-ray, CT, or an MRI scan.
How to Prevent Stress Fractures
Bone strength is key when it comes to preventing stress fractures, which is why researchers from Thomas Jefferson University have been studying screening options they hope female runners can one day use to understand their personal risk of injury. In the study they used a comprehensive blood panel as well as a survey on the runners’ nutrition, training intensity, strength training, and experience of pain to determine their risk of a stress fracture.
“This mixed methods approach provides a richer context and a more detailed picture of the practices and risks that contribute to stress fractures in every-day women runners,” says lead author Jeremy Close, MD.
How hard, how often, and where you train, as well as your nutrition can play a role in keeping you injury free. The researchers found that women with a history of stress fracture were more likely to report that they were not making time for strength training or a balanced diet.
Here are a few ways you can get on track to prevent injury.
Prevent injury with a structured training plan.
Following a structured training plan is very important. As mentioned above, stress fractures are often caused by intense training with not enough recovery built in. That’s why it is so important to increase your training gradually and follow a structured plan.
Many plans use something called periodisation where you increase your training over three weeks followed by a week of relative rest which allows the bones to recover. A running coach can help you put together a more personalized training plan that works best for your body and your skills to keep you injury free.
Mind the surfaces you run on.
Run on soft surfaces, if possible. Though they definitely have other hazards to them, dirt or loose gravel trails and sandy beaches are the softest in terms of impact. Treadmills, tracks, and roads are next on the hardness scale, with concrete sidewalks being the hardest. Most coaches will recommend running on a variety of surfaces instead of overloading on one.
Keep up on your calcium and vitamin D.
Good nutrition is essential for bone health. As well as maintaining an adequate calorie intake and normal BMI , we should all aim for around 1500mg calcium each day. Vitamin D is another essential micronutrient for sound bone health. And since we mainly get it from being in the sun, most people have a bit of a deficiency.
Before reaching for a supplement, try adding more calcium and vitamin D rich foods into your diet.
Sources of vitamin D:
- Fish oil
- Whole milk
Sources of calcium:
- Dairy, almond, and soy milk
- Mustard spinach
Sources of both:
- Fortified cereals
If you’re not sure you’re getting enough in your diet, a supplement could help; but ask a registered dietician or your physician for advice on this first.
Listen to your body.
As with any injury, it’s essential that you assess it sooner rather than later, so if you’re developing bone pain, get it checked out.
Treating Stress Fractures
According to Dr. Parthasarathy, it’s common for runners to avoid seeking treatment for stress fractures, but trying to continue running on this kind of injury can worsen it significantly.
The treatment of stress fractures vary depending on the type of fracture. Many can be managed by reducing sporting activity and adjusting risk factors, while some will need more intensive rehabilitation and even surgery.
Some fractures require a boot, surgical shoe, or stiff soled shoes. According to Dr. Parthasarathy, not wearing the prescribed footwear or continuing to run when you’re advised not to can not only affect the time it takes to heal, but could potentially turn a stress fracture into a complete break in the bone.
Remember, the sooner you begin treating the problem, the sooner you can come back as a stronger, healthier runner.