Exercise and sports injuries are common. After all, you’re putting your body under considerable stress when you work out. That’s what causes it to change – but overdo it and you could end up with an injury that makes it hard to work out for weeks or months. One of the most common of sports-related injuries are stress fractures.
Stress fractures most commonly involve the bones in the lower extremities including the feet, heels and lower legs, although they can also involve the pelvis and spine. Unlike a common fracture that occurs from trauma or a spontaneous break in a bone weakened by osteoporosis, stress fractures involve normal bones that have been overstressed, usually due to repetitive trauma. When bones are placed under repeated stress, they undergo remodeling, but if you keep stressing the bone without giving it enough time to rest, the repair and remodeling process can’t “keep up.” This causes tiny fractures to develop in the bone.
Are You at Risk for a Stress Fracture?
Females have a higher risk for stress fractures than males, especially women who over-train and eat a diet that’s low in calories, causing their estrogen levels drop. Estrogen is important for maintaining bone density and when bone density drops the risk of developing a stress fracture is increased. Other risk factors include smoking and excessive use of alcohol. Interestingly, low vitamin D levels have been linked with a greater risk for stress-related fractures.
One of the biggest risk factors for stress fractures is overtraining or a sudden increase in exercise volume, frequency or intensity. Runners who increase their mileage too quickly may pay for it with a painful fracture. That’s why it’s important to increase running distance by no more than 10% per week. It’s not just running that puts you at greater risk for a stress fracture, any kind of excessive high-impact exercise does too.
How Do You Know if You Have One?
Pain is the most common symptom of a stress fracture, but the discomfort of a stress fracture can be hard to distinguish from other overuse injuries like tendinitis. Swelling is another common symptom with both stress fracture and tendinitis. Typically the pain of a stress fracture is “point tenderness.” meaning the discomfort is aggravated when you press in one discrete spot. The pain of tendinitis is usually more diffuse and difficult to localize.
Sometimes doctors use the “tuning fork” test when they suspect a stress fracture. If you place a vibrating tuning fork over a sore area, it aggravates the pain if it’s a stress fracture, although this test isn’t 100% diagnostic.
Even when there’s a stress fracture, it won’t always show up on x-ray the first time. Sometimes it won’t be visible on x-ray until weeks later. That’s why some doctors order an MRI study when the x-ray is normal but they still suspect a fracture.
Can You Still Exercise with a Stress Fracture?
Stress fractures need time to heal but that doesn’t necessarily mean you can’t stay active. It’s important to avoid activity that aggravates the pain as well as a high-impact activity since most stress fractures involve the bones in the legs. With your doctor’s okay, it may be acceptable to cross-train or do low-impact exercise. Swimming and under-water running are good ways to maintain cardiovascular fitness until the fracture heals. Cycling is another low-impact activity that can help you stay in shape if you have a stress fracture. Talk to your doctor first.
Healing can take anywhere from several weeks to several months to be complete. Continuing to do high-impact exercise with a stress fracture delays the healing process and can lead to complications. Some doctors recommend wearing compression walking boots, a stirrup leg brace or crutches. Fractures involving certain parts of the foot take longer to heal and may benefit from a cast.
Stress fractures in certain areas have a higher risk of complications. These include fractures of the patella, tibia, medial malleolus, parts of the femur as well as tarsal, talus, fifth metatarsal or navicular fractures. Fractures in these areas have a higher risk of becoming full fractures and developing complications that delay healing.
How to Prevent Stress Fractures
The best way to prevent a painful, inconvenient stress fracture is to gradually increase the frequency or intensity of your exercise program and avoid doing the same activities over and over. Cross-train and use a variety of exercise DVDs to limit repetitive movements. Do regular strength-training to strengthen the muscles in your lower extremities and core exercises to strengthen the bones in your spine and pelvis.
Make sure you’re eating a nutritionally-sound diet and are consuming enough calories for your activity level. Give your bones the building blocks they need by eating a diet rich in calcium and foods that contain vitamin D like fatty fish and vitamin D fortified milk. Be sure you’re exposing your skin to sunlight several times a week to boost your vitamin D level. If you experience pain or point tenderness, see your doctor right away. Don’t exercise through the pain.
The Bottom Line?
Stress fractures are painful and inconvenient. Make sure you’re doing what you can to prevent them by not overtraining or increasing the volume, duration, frequency or intensity of your workouts too quickly. Don’t overdo the cardio and make sure you’re strength training.
References:
American Family Physician. January 1, 2011. Vol. 83, No. 1.
American Academy of Orthopedic Surgeons. “Stress Fractures of the Feet and Ankles”
