Running injury science

The ACWR Rule That Prevents 80% of Running Injuries

80% of running injuries are overuse injuries caused by training load errors. One number, the Acute-to-Chronic Workload Ratio, predicts most of them.

Second Injury Syndrome: Why Runners Get Hurt Again in Week 6

You finished your return-to-running plan. Everything feels great. Then, 6 weeks later, you're injured again. This isn't bad luck. It's a predictable pattern.

Why 'Start Slow' Is Terrible Injury Advice

Every runner coming back from injury hears the same thing: "start slow." It sounds sensible. It's completely useless as actionable guidance.

IT Band Syndrome Recovery Time: What the Research Actually Shows

IT band syndrome recovery time varies from 4 weeks to 6 months depending on factors most runners never consider. Here is what the research says about realistic timelines.

Running with a Stress Fracture: Why You Cannot Train Through This One

Stress fractures sit on a different tier from most running injuries. Unlike tendinopathy or muscle strains, continuing to run on a stress fracture risks turning weeks of recovery into months.

The 10% Rule and Plantar Fasciitis: Why It Falls Short for Recovery

The 10% rule is the default advice for mileage progression, but it was never designed for injury recovery. For plantar fasciitis, a more precise approach produces faster, safer returns.

How to Calculate Acute Training Load for Running

Acute training load is the numerator in the ACWR equation. Understanding how it is calculated, and why the method matters, helps you make better decisions about when to push and when to back off.

How Much Should You Increase Mileage Per Week?

The answer is not 10%. It is not any fixed percentage. How much you can safely increase depends on your individual training history, and there is a better way to find the right number.

Running After Plantar Fasciitis: What to Expect Your First Month Back

You have been cleared to run again after plantar fasciitis. Now what? The first month back is a confusing mix of optimism, paranoia, and morning heel checks. Here is what to expect.

Running After Achilles Tendonitis: A Realistic Timeline

Your Achilles has calmed down enough to start running again. But the return is where most runners get it wrong — pushing too fast because the tendon feels fine, then paying for it a week later.

Running After a Stress Fracture: The Honest Timeline

You have medical clearance to start running again after a stress fracture. The next 8 weeks are the most important of your return — and the most commonly botched.

What Is ACWR? The Runner's Guide to Injury Prevention's Most Useful Number

The Acute-to-Chronic Workload Ratio sounds complicated. It is not. It is one number that tells you whether your recent training is safe or risky. Here is how it works.

How Long Do Shin Splints Take to Heal? (It Depends on What You Do Next)

Shin splints are the most common injury in distance running, and the recovery time ranges from 2 weeks to 6 months. The difference is almost entirely determined by what you do in the first 2 weeks after symptoms appear.