What Happens When You Run a Marathon Without Proper Training?

jeff gaudette
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Female Runner Clutching Injured Knee


It seems like everyone is training for a marathon these days, and the pressure to run one can seem daunting. However, is it possible that training for and racing a marathon might not be in your best interest?

In this article, we'll look at the potential pitfalls of training for and racing a marathon when you're not prepared, and how this might be a detriment to your short-term and long-term development.

Let me preface this article by stating that I am not implying that running a marathon can't be done if you don't have the training background. I am merely making the argument that it might not be the best goal for you if you have long-term aspirations with your running.

More: How Much Marathon Training Do You Really Need?

Do you have the training background and time available to prepare yourself?

The marathon is an arduous event and requires a dedicated training block of at least four months for beginning runners (classified as someone running consistently for less than a year, or averaging less than 20 to 25 miles per week). More importantly, training for a marathon when you don't have the requisite running background is a sure fire way to get injured or find yourself disenchanted with running if you're new to the sport.

More: 7 Ways to Prepare for Your First Marathon

Suggested Running Level to Start Marathon Training

In my experience, beginners need to be able to average at least 30 to 35 miles per week for 5 to 6 weeks to increase the chance that they will have a good race experience. This means that you need to be able to run 25 to 30 miles per week comfortably before you begin training for a marathon.

If you're not at this number, it doesn't mean you can never train for a marathon. Rather, you should focus on slowly building your training tolerance and mileage. Otherwise, you're probably going to struggle to increase the weekly mileage and long runs enough to be prepared on race day.

More: How to Train for Your First Marathon