If you have ever been running and started feeling an aching or painful sensation along your shin, there is a good chance you have wondered the same thing many runners do: Why do I keep getting shin splints?
Shin splints are one of the most common lower-leg problems among runners and other athletes who participate in repetitive, high-impact activities. They can range from a minor annoyance at the beginning of a run to enough pain that continuing to train becomes difficult.
I have dealt with shin splints multiple times throughout my own running career, especially during track season. Over the years, I have learned that there usually isn’t one single reason they develop. Training load, running surface, biomechanics, recovery, footwear, and previous injuries can all play a role.
This article covers what shin splints are, what causes them, and why certain runners may be more likely to develop them.
Disclaimer: I am not a medical professional, and this article is for educational purposes only. My personal experience with running injuries does not replace evaluation or treatment from a qualified healthcare professional.
What Are Shin Splints?
“Shin splints” is the common name for medial tibial stress syndrome (MTSS). It generally causes exercise-related pain and tenderness along the tibia, or shinbone, most commonly along the inner portion of the lower leg.[1][2]
The pain does not necessarily feel the same for everyone. Some runners describe it as an ache or soreness, while others experience more significant discomfort during or after running.
Early on, shin splint pain may appear primarily while exercising and improve after you stop. If the condition continues to worsen, the area may become increasingly tender and pain may last longer after exercise.[1]
One important distinction is that not every pain in your shin is a shin splint. Stress fractures, muscle injuries, and conditions such as chronic exertional compartment syndrome can also cause lower-leg pain.
Pain that is very localized to one small spot, becomes severe, occurs while resting, or continues to worsen should not automatically be assumed to be shin splints. Those symptoms are a good reason to stop training and talk with a healthcare professional.
What Actually Causes Shin Splints?
Shin splints are considered an overuse injury.
Running places repeated loads on your legs every time your foot contacts the ground. Your bones, muscles, tendons, and other tissues normally adapt to those stresses over time. That stress is actually part of how your body becomes stronger.
Problems can begin when the amount of stress being placed on the lower leg starts exceeding what the tissues are currently prepared to handle.
That could happen because you suddenly:
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Increase your weekly mileage
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Start running more frequently
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Add harder workouts
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Begin sprinting
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Add hills
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Start a new sport
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Return to running after taking time off
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Transition to a different training surface
Medial tibial stress syndrome appears to involve repetitive stress on the tibia and the tissues surrounding and attaching to it.[1][2] Rather than thinking of shin splints as simply “inflammation,” it is more accurate to think of them as a load-related stress injury involving the lower leg and tibia.
This is why managing your training load is so important.
Why Do Runners Get Shin Splints?
There isn’t always one obvious cause. Usually, several factors come together.
1. Increasing Your Training Too Quickly
One of the easiest ways to overwhelm your legs is to increase your training faster than your body can adapt.
Imagine someone who has only been running for two weeks. They may feel cardiovascularly capable of running farther or faster, but that does not necessarily mean the bones and connective tissues in their legs have adapted to that workload yet.
Then they suddenly add hard intervals, longer runs, or several extra days of training.
Their fitness may be ready for it.
Their shins may not be.
The Mayo Clinic lists sudden increases in the duration, frequency, or intensity of exercise among the factors that can increase the risk of developing shin splints.[1]
This is also why conditioning before a competitive season can be so important. Going from relatively little running directly into repeated high-intensity workouts places a much different demand on the body than gradually building up to them.
2. Repetitive Impact From Running
Running involves thousands of individual foot strikes.
Your body is designed to tolerate impact, so impact itself isn’t automatically bad. The problem occurs when the total amount of stress exceeds your body’s ability to recover and adapt.
That is also why simply saying that running “causes shin splints” isn’t quite right. Millions of people run without developing them.
The better question is whether your current amount of running exceeds what your body is prepared for.
That difference matters.
3. Running on Hard Surfaces
Hard surfaces such as pavement and concrete are commonly associated with shin splints, and running on hard or uneven surfaces is listed as a potential risk factor by the Mayo Clinic.[1]
From personal experience, this has always been noticeable for me. I have historically been much more likely to experience shin splints during track season than during cross country season.
However, I would not say that running on pavement or a track automatically causes shin splints.
Surface is only one part of the picture.
A runner who has gradually adapted to road running may handle pavement perfectly well, while another runner who suddenly changes from low-impact training to high-mileage road running may have problems.
Your total workload and how prepared your body is for that workload matter just as much, if not more.
4. Foot Mechanics and Pronation
You may have heard that overpronation causes shin splints.
This needs a little clarification.
Pronation is a normal movement of the foot. Your foot naturally rolls inward to some degree as it absorbs force during walking and running. It does not automatically mean anything is wrong with your stride.
However, certain foot mechanics appear to be associated with a greater risk of medial tibial stress syndrome.
One of the better-studied measurements is navicular drop, which is related to how much the arch of the foot changes when weight is placed on it. Systematic reviews have found that greater navicular drop is associated with an increased risk of developing medial tibial stress syndrome.[3][4]
That does not mean everyone who pronates needs corrective shoes.
It also doesn’t mean buying a stability shoe will automatically fix shin splints.
Shoes, orthotics, running mechanics, strength, training history, and individual anatomy all have to be considered together. If you repeatedly experience shin splints and suspect your running mechanics are contributing, it may be worth having your gait evaluated by a qualified physical therapist, sports medicine professional, or other professional experienced with runners.
5. Previous Running Injuries
Your injury history matters too.
A systematic review and meta-analysis published in Sports Health identified previous running injury as one of several factors associated with an increased risk of medial tibial stress syndrome.[4]
This is something runners often overlook.
Once the pain disappears, it is tempting to immediately return to the same mileage and intensity you were doing before the injury. But being pain-free doesn’t necessarily mean you should jump straight back into your previous training load.
A gradual return gives your body time to rebuild its tolerance.
6. Individual Anatomy and Other Risk Factors
Some runners simply have more risk factors than others.
Research has found associations between medial tibial stress syndrome and factors including:
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Greater navicular drop
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Previous running injuries
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Higher body weight
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Female sex
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Certain hip-motion characteristics[3][4]
These factors shouldn’t be interpreted as guarantees that someone will develop shin splints. They simply appear more frequently in people who develop MTSS when groups of athletes are studied.
This is another reason there is no single “shin splint fix” that works for every runner.
Can Shin Splints Turn Into a Stress Fracture?
Shin splints and tibial stress fractures are different conditions, but they exist within the broader spectrum of bone stress injuries.
Continuing to overload a painful tibia without giving it enough opportunity to recover may allow the problem to become more serious. Persistent symptoms should therefore not be ignored.[1][2]
One clue doctors use when distinguishing the two is the pattern of tenderness. Shin splint pain tends to be more diffuse, meaning it covers a broader area along the shin. A stress fracture may produce more focal pain in one specific location.
That isn’t something you should try to diagnose solely from an article, though.
If your pain becomes severe, extremely localized, occurs during normal walking or while resting, or fails to improve after reducing your activity, getting evaluated by a medical professional is the safer option.
Do You Have to Stop Running With Shin Splints?
Not necessarily forever, but you do need to address the activity that is aggravating the injury.
The goal is to reduce the stress on the lower leg enough for it to recover.
For some runners, that could mean completely stopping running temporarily. For someone with mild symptoms, it may mean reducing mileage or eliminating high-intensity workouts while replacing some running with lower-impact activities.
Swimming, cycling, and other forms of cross-training can sometimes allow you to maintain cardiovascular fitness while decreasing repetitive impact on the tibia.[5]
Trying to push through worsening shin pain is generally not a good training strategy.
There is a difference between the normal discomfort of a difficult workout and pain from an injury.
My Experience With Shin Splints
Shin splints used to feel almost inevitable for me during track season.
They typically appeared much more often during track than during cross country. The difference between running on a track and running on softer cross-country terrain seems like a simple enough answer.
The explanation is more complicated.
Surface probably contributed, but so did the way the seasons were structured. Cross country generally involved a larger aerobic base and more gradual conditioning. Track introduced faster running, sprinting, intervals, and repetitive high-intensity sessions.
That combination can create a rapid change in the amount and type of stress being placed on your legs.
This is one of the biggest lessons I have learned from dealing with shin splints repeatedly:
Your body needs time to adapt to the type of training you’re asking it to do.
You cannot completely eliminate the possibility of getting injured, but smart progression gives your body a much better chance of keeping up with your training.
The Bottom Line
So, why do runners get shin splints?
Usually, it comes down to repetitive stress exceeding what the lower leg is currently prepared to tolerate.
Suddenly increasing your mileage or workout intensity, changing your training environment, your individual biomechanics, previous injuries, and other physical characteristics can all affect your risk.
The biggest mistake is assuming shin splints are simply part of being a runner and continuing to train through worsening pain.
They are common, but they shouldn’t be ignored.
If you’re already dealing with shin pain, read How to Treat Shin Splints next. If you’re currently healthy and want to reduce your chances of developing them, check out How to Prevent Shin Splints.
Those articles go deeper into what you can do before and after shin splints develop so you can spend less time worrying about your shins and more time training.
Sources
[1] Mayo Clinic. Shin Splints — Symptoms and Causes. Updated April 30, 2025. Mayo Clinic.
[2] Deshmukh NS, Phansopkar P. Medial Tibial Stress Syndrome. StatPearls Publishing, National Library of Medicine.
[3] Newman P, Witchalls J, Waddington G, Adams R. Risk Factors Associated With Medial Tibial Stress Syndrome in Runners: A Systematic Review and Meta-Analysis. Open Access Journal of Sports Medicine. 2013;4:229–241.
[4] Reinking MF, Austin TM, Richter RR, Krieger MM. Medial Tibial Stress Syndrome in Active Individuals: A Systematic Review and Meta-analysis of Risk Factors. Sports Health. 2017;9(3):252–261.
[5] Mayo Clinic. Shin Splints — Diagnosis and Treatment. Updated April 30, 2025. Mayo Clinic.