"Shin splints" is a catch-all term for medial tibial stress syndrome (MTSS) — pain along the inner border of the shinbone, usually in runners, walkers, dancers, and military recruits who've ramped up training too quickly.
What's actually happening
The tissue that connects your deep calf muscles to the tibia becomes inflamed and irritated from repetitive tibial bending. Ignore it long enough and it progresses to tibial stress reaction, then to a stress fracture — which sidelines you for months.
Common triggers
- Sudden increase in mileage or intensity
- Hard surfaces (concrete over trails)
- Worn-out running shoes
- Tight calves, weak glutes and hips
- Overpronation or poor foot mechanics
- Low bone density (especially in female runners with menstrual irregularities)
How to tell it's not a stress fracture yet
MTSS pain is usually diffuse along a 5cm+ region of the inner shin. Stress fracture pain is more focal — a single tender spot that hurts to hop on one leg. If a single point is very tender, or if pain is present at rest, get imaged.
What actually helps
Load management — drop mileage 30-50%, cross-train with swimming or cycling, and rebuild slowly. Running through MTSS almost always makes it worse.
Calf, tibialis posterior, and intrinsic foot strengthening — the muscles that absorb impact and control pronation.
Glute medius and hip strength — most shin issues have an upstream hip weakness component.
Shockwave therapy — strong evidence for chronic MTSS that hasn't responded to conservative care.
Footwear and orthotic assessment — sometimes a shoe change or a properly-made custom orthotic is the difference-maker.
Return-to-run rules
No pain during runs. No pain the day after. Progress by no more than 10% per week. If pain returns, back off two weeks.
Get seen if pain is focal, present at rest, or lingers more than 2-3 weeks despite load reduction.