A Complete Guide to Shin Splints

You sign up for a marathon, triathalon, or even your very first 5K race, and begin running. A few weeks in, you notice a niggling pain in your lower leg. Bad news: It's likely shin splints, one of the most common endurance training injuries. Good news: It's not that serious.

Read on for the symptoms, treatment, and prevention of shin splints, plus anything else you need to know.

What Are Shin Splints?

Shin splints, also known as medial tibial stress syndrome (MTSS), is inflammation in one of your shin muscles where it attaches to the tibial bone (the large bone in your lower leg). It can happen on the front of your shin (the tibialis anterior muscle) or the inside of your shin (tibialis posterior muscle), says Robert Maschi, D.P.T., a physical therapist and associate clinical professor at Drexel University.

The tibialis anterior muscle lowers your foot to the ground and the tibialis posterior muscle controls pronation of your foot (lowering your arch, or the inside of your foot, toward the ground). In general, shin splints are discomfort in the front of the lower leg during exercise. The pain is usually caused by micro-tears in the muscle where it attaches to the bone.

What Causes Shin Splints?

Shin splints are technically a strain injury and are most common in runners (although it can occur from excessive cycling or walking, too). There are lots of different causes of shin splints including physical traits (small calf muscle circumference, poor ankle mobility, weak hip muscles), biomechanics (running form, excessive pronation), and weekly mileage, says Brett Winchester, D.C., and advanced biomechanics instructor at Logan University's College of Chiropractic.

Since shin splints are caused by stress overload, they often happen when you run too far, too fast, too soon, says Maschi. It's the consequence of literally going from 0 to 60.

Medically, a repetitive trauma in the same area leads to inflammation, explains Matthew Simmons, M.D., a sports medicine physician at Northside Hospital Orthopedic Institute. When the amount of inflammation exceeds your body's ability to adequately heal (especially if you don't stop the activity causing it), it builds up in the tissues, leading to irritation of the tendons, muscles, and bones. That's when you feel the pain.

How Do You Treat Shin Splints?

The phrase no runner wants to hear: rest days. Since shin splints are an overuse injury, the best course of action is to avoid continued stress of the area—which usually means time away from running, says Dr. Simmons. During this time, you can cross-train, strength train, foam roll, and stretch.

Over the counter medications (like Motrin and Aleve), ice, compression, and acupuncture are proven methods to help reduce the pain and inflammation caused by shin splints. If it doesn't subside in two to four weeks, head to your doc or physical therapist for more advanced treatment.

To prevent the reoccurrence of shin splints, you'll need to address the cause, not just the symptoms. Because there are so many possible causes it can be difficult to pinpoint and may require physical therapy sessions to identify and fix. Physical therapy could address flexibility and mobility (of the calf, foot, and ankle), strength (foot arch, core, and hip muscles), or form (strike pattern, cadence, and pronation), says Maschi.

What Happens if Shin Splints Aren't Treated?

Shin splints are NBD if you rest up. But if you don't? You'll have more serious issues at hand. If shin splints are left untreated and/or you continue running on them, the bone may start to break down, which will become a stress fracture. You'll want to avoid that at all costs since a fracture of the tibia requires four to six weeks of complete rest and recovery and may also necessitate a walking boot or crutches. A few days or weeks off running is way better than months of recovery.

How Can You Prevent Shin Splints?

If you train for big endurance races, a small injury may be inevitable, but knowing what causes shin splints and how to prevent them, will keep you healthy and get you back out pounding the pavement faster.

Start slow. Ramp up your running slowly by gradually increasing mileage and speed. Maschi recommends increasing your running duration or distance by a maximum of 10 to 20 percent per week. (Ex: If you ran a total of 10 miles this week, don't run more than 11 or 12 miles next week.) He also adds that switching to orthotics or motion-control shoes can reduce excessive pronation and improve the load on the tibialis posterior (reminder: that's the muscle on the inside of your shin). (Plus, make sure your running shoes have these two game-changing qualities and that you're not running in old shoes.)

Check your running form. Striking the ground with your foot too far forward is a common biomechanics error. "Fixing form so the strike point is underneath your hips will prevent shin splints in many cases," says Winchester. Tight hips or weak glutes are often the culprit, as you're driving forward with your lower legs and feet rather than your hips and glutes.

Stretch—and stretch enough. Stretching can't prevent shin splints on its own, but it can improve factors that lead to shin splints. For example, a tight Achilles tendon or tight hips can cause abnormal running mechanics, and that improper form can lead to overuse injuries, says Dr. Simmons.

After having shin splints, you may also benefit from stretching the muscles around the shin to allow a return to normal mechanics. Incorporate a standing calf stretch and seated dorsiflexor stretch (sit with a band or towel looped around your foot, and flex your toes back toward your shin) into your routine, says Maschi.

Doing one stretch for 5 or 10 seconds pre-run isn't quite enough: Ideally, you'll stretch your lower legs in multiple planes and dynamically, says Winchester. For example, do these calf stretches for 10 reps, 3 to 5 sets every day for the best results.

Don't forget to cross-train. Running might be your thing, but it can't be your only thing. Yes, this can be difficult when all your time is spent training for an endurance race but remember a consistent strength training and stretching routine are must-haves for a healthy runner. Your power should come from your core and glutes, so strengthening these areas will improve running mechanics and help to avoid injury to weaker areas, says Maschi. (Try a running-related weight training plan like this ultimate strength workout for runners.)

To specifically strengthen the muscles of the lower leg (which might be short and tight, as a result of shin splints), add calf raises into your routine. While standing, raise up on your toes on a one-second count and lower to the ground on a three-second count. The eccentric phase (going back down) is critical for the exercise and should be done slowly, says Winchester. (