Shin splints often plague runners who don’t build their mileage up gradually, or those who make an abrupt change to their workout regimen, like switching from running on grass to concrete, for example. Also known as medial tibial stress syndrome (MTSS), shin splints is the catch-all term for lower leg pain that occurs below your knee, either on the front outer part of your leg (anterior shin splints) or the inside of your leg (medial shin splints).

But what exactly are shin splints? Unfortunately, there’s no concrete consensus among sports scientists. Some theories hypothesis this pain is a result of small tears in the muscle that’s pulled off the bone, an inflammation of the periosteum—a thin sheath of tissue that wraps around the tibia a.k.a. the shin bone—an inflammation of the muscle, or some combination of all of these.

Regardless, the nature of shin splints most often can be captured in four words: too much, too soon.

How do you know if you have shin splints?

Shin pain doesn’t always mean you have shin splints. It might be a sign of some other problem. The following are two conditions that are sometimes mistakenly diagnosed as shin splints.

Pain on the anterior (outside) part of the lower leg may be what’s called compartment syndrome—a swelling of muscles within a closed compartment—which creates pressure. To diagnose this condition, special techniques are used to measure the amount of pressure. Sometimes surgical “decompression” is required. The symptoms of compartment syndrome include leg pain, unusual nerve sensations, and eventually muscle weakness.

You can typically tell the difference between compartment syndrome and shin splints because compartment syndrome is more progressive in that it gets worse as you run and the onset happens earlier and earlier, with relief only coming from rest. Shin splint pain, on the other hand, typically happens at the start of a run, but gets better as muscles warm up (though it may return again as muscles fatigue).

    Pain in the lower leg could also be a stress fracture (an incomplete crack in the bone), which is a far more serious injury than shin splints. An MRI is the definitive method for diagnosing a stress fracture.

    The pain of shin splints is usually more generalized than that of a stress fracture. Press your fingertips along your shin, and if you can find a definite spot of sharp pain, that’s more commonly a sign of a stress fracture. If, over a period of time, the pain comes on earlier in your runs and walks, it might be a stress fracture.

    Additionally, stress fractures often feel better in the morning because the bone has rested all night; shin splints often feel worse in the morning because the soft tissue tightens overnight. Shin splints are also at their most painful when you flex your ankle or bring your toes toward your shin.

    If pain progresses from running to simply walking, it could be a stress fracture and that definitely means it’s time to see a doctor.

    What causes shin splints?

    There can be a number of factors at work that are causing shin splints, such as overpronation (a frequent cause of medial shin splints), inadequate stretching, worn shoes, or excessive stress placed on one leg or one hip from running on cambered roads or always running in the same direction on a track.

    Typically, one leg is involved, and it is almost always the runner’s dominant one. If you’re right-handed, you’re usually right-footed as well, and that’s the leg that’s likely to hurt.

    Flat feet can sometimes contribute to shin splints, but this is more likely to be the case if your feet have changed over time (arches tend to flatten with age). A prior injury, especially if it affects mechanics, can also cause shin splints.

    The most common site for shin splints is the medial area, which is the inside of your shin. Anterior shin splints, which are located toward the outside of your leg, usually result from an imbalance between your calf muscles and the muscles along the front of your leg and often afflict beginners who either have not yet adjusted to the stresses of running or are not stretching enough.

    How can you treat shin splints?

    Experts agree that when shin splints strike, you should stop running completely or decrease your training depending on the extent and duration of pain.

    Then, as a first step, ice your shin to reduce inflammation, says Jordan Metzl, M.D., a sports medicine physician at the Hospital for Special Surgery in New York City, creator of Runner’s World’s IronStrength workout, and coauthor of The Athlete’s Book of Home Remedies.

    Here are some other treatments you can try:

    • Gently stretch your Achilles if you have medial shin splints, and your calves if you have anterior shin splints. Try this stretch for your shins: Kneel on a carpeted floor or exercise mat, legs and feet together and toes pointed directly back. Then slowly sit back onto your calves and heels, pushing ankles into the floor until you feel tension in the muscles of your shin. Hold for 10 to 12 seconds, relax, and repeat.
    • Start in a seated position, then trace the alphabet on the floor with your toes. Do this with each leg. Or alternate walking on your heels for 30 seconds with 30 seconds of regular walking. Repeat four times. These exercises are good for both recovery and prevention. Try to do them three times a day.
    • If you continue running, wrap your leg before you go out. Use either tape or an Ace bandage, starting just above the ankle and wrapping to just below the knee. Continue wrapping your leg until the pain goes away, which usually takes three to six weeks. “What you’re doing is binding the tendons up against the shaft of the shin to prevent stress,” Metzl says.
    • Consider cross-training for a while to let your shin heal. Swim, run in the pool, or ride a bike.
    • Foam roll your shins to loosen up the muscles, says Metzl.
    • When you return to running, increase your mileage slowly, no more than 10 percent increase in distance each week.
    • Avoid hills and excessively hard surfaces until shin pain goes away completely, then re-introduce them gradually to prevent a recurrence.

    How can you prevent shin splints?

    There are numerous things you can do to lower your chances of getting shin splints:

    • Make sure you wear the correct running shoes for your foot type. If you’re unsure, visit your local running store to get a professional fit or analysis.
    • Have two pairs of shoes and alternate wearing them to vary the stresses on your legs.
    • If you frequently run on roads with an obvious camber, run out and back on the same side of the road. Likewise, when running on a track—switch directions.
    • Strength train. “Good strength will keep you running in proper form and alignment, and that will help a lot,” Metzl says. He recommends exercises like jump squats, split squats, and single-leg toe touches.
    • If you know you are prone to developing shin splints, stretch your calves and Achilles regularly as a preventive measure.
    • Take in foods that are high in calcium and vitamin D, which will improve bone density, Metzl adds. This is especially true if you are a woman with a family history of osteoporosis.
    • Work with a physician or dietitian to make sure you’re getting adequate protein intake to recover from runs and workouts.
    • Shorten your stride and quicken cadence. Metzl suggests keeping your cadence between about 85 to 90 steps per minute (with one foot). This can help to prevent overstriding.
    Headshot of John Vasudevan, M.D.
    Medically reviewed byJohn Vasudevan, M.D.
    Sports Medicine Director & Medical Advisor

    John Vasudevan, M.D. is an associate professor at the University of Pennsylvania. He is board-certified in Physical Medicine & Rehabilitation and Sports Medicine. He is a Team Physician for UPenn Athletics and  medical director of the Broad Street Run and Philadelphia Distance Run, and previously for the Rock 'n' Roll Half-Marathon and Tri-Rock Triathlon in Philadelphia. He is a director of the running and endurance Sports Medicine Program at Penn Medicine.  Dr. Vasudevan provides non-operative management of musculoskeletal conditions affecting athletes and active individuals of all levels, and combines injury rehabilitation with injury prevention. He utilizes a variety of ultrasound-guided procedures and regenerative approaches such as platelet-rich plasma and percutaneous ultrasonic tenotomy. He sees patients at the Penn Medicine and the Philadelphia Veterans Administration hospital. Dr. Vasudevan attended medical school at the University of Wisconsin School of Medicine and Public Health in Madison. After his Transitional Year in Tucson, Arizona, he went to residency in PM&R at Thomas Jefferson University in Philadelphia and onwards to Stanford University for his fellowship in Sports Medicine. He has been in practice at the University of Pennsylvania since 2012.