Everyone’s had them at some point in their running life. Shin Splints have become kind of a catch-all term for discomfort in the lower leg. But did you know that there are two specific ailments that the term ‘Shin Splint’ describes – anterior and posterior. Today we’ll discuss Medial Tibial Stress Syndrome (Posterior Shin Splints).
WHAT’S THE PAIN LIKE?
Described as acute (the painful kind of pain) during the run; dull (the sore, throbbing kind of pain) after the run and throughout the day. Many people report tenderness along the medial side of the lower leg when gentle pressure is applied to a localized spot 2-3 inches above the ankle.

A bone scan shows the area of inflammation associated with Posterior Shin Splints
MAIN CAUSES
Once thought of as a soft tissue injury, Posterior Shin Splints have actually been proven to be a bone injury. So here’s how they occur:
Our bones aren’t made of concrete – they are actually flexible and porous. So when you run, your tibia bends slightly on impact – like a thin steel rod under a compressive load. In response to the stress of running, bone becomes stronger – but it takes time. This is the same way that your muscles get stronger – by repairing hundreds of micro-injuries sustained during stress.
HOWEVER, if the body’s ability to remodel the bone is outpaced by stress – from running in our case – your body cannot repair itself quickly enough. Weakness builds along a specific impact spot on the tibia, leading to acute pain.
So to put it simply, Posterior Shin Splints are primarily an overuse injury.
They can, though, be hastened by other factors:
MUSCLE WEAKNESS or IMBALANCE – seems to factor in pretty much every running-related injury, doesn’t it?! It’s not enough to just run. You have to cross-train and strengthen as well. In the case of Posterior Shin Splints, calf and hip weakness seems to be a primary aggravator. Your calf muscles help brace the tibia against impact and strong hip muscles help your body attenuate impact during every run.
WEAK BONE DENSITY – if you have existing risk factors for low bone density, you may be more likely to encounter Posterior Shin Splints. Risk factors include being female, of Northern European descent, or having a diet low in calcium and vitamin D. Weight-bearing exercises can help build your bone density.
UNSUPPORTED OVERPRONATION – overpronation loads more force onto the inner side of the tibia. Make sure you’re wearing the proper amount of support in your running shoes, especially if you are new to running.
HOW DO I GET RID OF THEM?
Alleviating and recovering from Posterior Shin Splints requires PATIENCE. Basically the only way to get rid of them is to dramatically reduce your training for a period of time. You need to give your tibia time to repair and rebuild bone density on that weak spot.
TO ADDRESS PAIN: ice may help alleviate some discomfort. Do 15 minutes on about four to six times per day. Take an anti-inflammatory if you feel comfortable doing so. Anti-inflammatories mask pain though, so be careful that you’re not returning to training too quickly.
Switch to low- or non-impact activities for a little while (cycling, swimming, etc) and work on building your lower body strength in the meantime. Once the pain is no longer acute, try and gradually return to running.
Work on your calves! Building calf strength and flexibility will help your tibia better brace against impact as you strike the ground while you run. Try using The Stick or a Thera-Roll to roll out those tight calves.
Try wearing compression socks during and after activity. Compression enhances blood flow, leading to more efficient oxygen delivery to your muscles. Your cells need oxygen to function and recover optimally, so compression helps enhance performance and recovery.

Stretching and strengthening can help you better avoid running-related injuries
HOW DO I PREVENT THEM?
Follow the 10% rule – increase your mileage total by no more than 10% each week. This gives your bones adequate time to remodel and strengthen.
Make sure your running shoes are properly supportive! Stop by your nearest Marathon Sports location to be properly fit for a pair of running shoes.
DO NOT run through pain. Learn how to identify the difference between discomfort and pain. If it just feels tight, go ahead and continue training. If you’re experiencing the acute pain in the leg location described above, reduce or stop your training and address it.
Work on lower body strength, specifically in the calves and hips. Mix in some calf raises, squats, lunges, and core work. Being a runner means you have to do more than just pound the pavement if you want to run comfortably for a lifetime.
If your shin splints always seem to crop up on one specific side of the body, make sure you’re switching up the side of the street that you’re running on (because the camber of the sidewalk can consistently put pressure on one side of the body).
Information for this post was adapted from RUNNING STRONG by Dr. Jordan Metzl and INJURY-FREE RUNNING by Dr. Thomas Michaud.