Shin Splints: What’s Actually Going On?

In the clinic, I commonly see athletes presenting with pain along the inner or outer aspect of the shin. This is often linked to a sudden increase in training load—for example, deciding to train for a marathon in a few months after not running consistently for the past year.

When training volume or intensity increases too quickly, it can exceed the tissue’s ability to adapt. This imbalance between stress and recovery can lead to what is commonly referred to as “shin splints.”

Shin Splints: More Than One Diagnosis

“Shin splints” is a broad term that actually covers four related conditions, all of which exist along a continuum. Depending on where you fall on this spectrum, management—and your ability to continue training—may differ.

1. Tibialis Anterior or Posterior Strain
This involves small tears in the muscles that originate along the shin and attach into the foot. These muscles play an important role in controlling foot and ankle mechanics during running.

2. Medial Tibial Stress Syndrome (MTSS)
This condition involves irritation or tearing of the connective tissue (fascia) along the inner shin. Unlike more serious injuries, pain often feels worse at the start of activity and improves as the session continues.

3. Stress Reaction
Here, the outer layer of the bone (where tendons and connective tissue attach) begins to swell and structurally weaken. Symptoms typically worsen with activity. A classic sign is tenderness over a broader area (greater than 5 cm) and pain with vibration.

4. Stress Fracture
This represents the final and most severe stage, involving a small break in the bone. Symptoms include sharp, localized pain (less than 2 cm in size) and pain with weight bearing or impact.

Health Tips:

Get imaging if symptoms are persistent or severe

X-rays may not show changes until weeks or months after symptoms begin since it does not show changes to soft tissues, only to the bone (ie stress reaction and fractures)
Ultrasound is increasingly used to detect soft tissue changes around the bone and is being increasingly used to help identify early stages of the injury.
MRI is the most sensitive option and is considered the gold standar, but hard to get in a timely manner.

Re-plan your training
Shin splints usually develop when training stress far exceeds recovery. Reducing volume and intensity allows tissues time to heal and adapt.

De-load without de-conditioning
Maintain cardiovascular fitness by cycling, swimming, or using an arm ergometer while reducing or avoiding running.

Support bone health through nutrition
Adequate intake of calcium and vitamin D is essential for maintaining bone density and supporting the body’s ability to tolerate repetitive loading.