Why is my half marathon training plan three miles short?

I'm training for my first half marathon. I found a beginner program from Hal Higdon that says my longest run leading up to the race should be 10 miles. Why is that? Three additional miles sounds like A LOT. Will I be ok if I only run 10 before race day?

Yes, you'll be ok.

I know it's kind of weird, like you're going into a test not fully prepared, but trust the wisdom of experienced coaches and runners alike, you'll be fine.

Physically, if your heart and lungs can do 10 miles they can certainly do 13 and even 26 (or longer). But your cardiovascular conditioning isn't the limiting factor in determining how far you can run once you get to these distances.

Endurance races demand that our muscles and bones are also up to the challenge. You're body must be able to tolerate and dissipate a LOT of force over the course of a simple short run, never mind an long road race. Good news: if you've trained properly and have completed 10 miles injury-free, you're going to be fine for 13.

Still unsure?

Ok, fine, I'll confess. Coaches are looking out for the health and success of our athletes – but also ourselves. If an athlete gets injured on our watch, no one wins. So, we've got to compromise and prescribe only the training that is necessary and nothing more. We've got to prepare you mentally and physically, but also get you to the starting line healthy.

As a beginner, you likely haven't yet built up your body to the point where it makes sense to run farther in training without increasing injury risk. Trust your training and look forward to more mileage in your next training program!

John Goldthorp is the founder of Fix Your Run, a specialized fitness coaching business that helps runners become faster and less prone to injury. Recently named "Philly's Best Running Coach" by Philadelphia Magazine, he currently works with clients at Optimal Sport 1315 in Center City, online at FixYourRun.com, and leads weekly group speed training sessions at PhillySurgeRunning.com.

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