Chasing 13.1: Why Your Half Marathon Training Might Be Stalling (And How to Fix It)

So, you’ve decided to tackle 13.1 miles. Whether you’re eyeing the Denver Colfax Half Marathon in May or another half marathon, signing up is the easy part. Training for a half marathon is a transformative journey, but it’s also one where small mistakes can lead to big setbacks.

As a run coach based in Denver, I see runners of all levels—from those just starting their habit to seasoned athletes looking to shave minutes off their PR—hit the same roadblocks. The good news? Most of these "training traps" are entirely avoidable with a little strategy and support.

Let’s dive into the most common half marathon training mistakes and, more importantly, how you can sidestep them to cross that finish line feeling strong and healthy!

1. The "Too Much, Too Soon" Trap

It is incredibly easy to get swept up in the excitement of a new training block. You feel great during week two, so you decide to add five extra miles to your long run or sprint every interval. However, your cardiovascular system often adapts faster than your bones, tendons, and ligaments.

Research shows that nearly 50% of regular runners experience an injury each year, with a staggering 70% to 80% of those being overuse injuries. Jumping from 10 miles a week to 25 too quickly is a recipe for an injury.

The Fix: Follow a structured plan that roughly follows the "10% Rule"—never increasing your weekly mileage by more than 10% at a time. If you’re feeling unsure about how to build safely, I can provide an individualized plan tailored specifically to your current fitness level, available time and injury history.

2. The Myth of the "Lone Wolf"

Running is often seen as a solitary sport, but training in a vacuum is one of the quickest ways to lose motivation. When the alarm goes off at 6:00 AM on a chilly Tuesday, it’s much easier to hit snooze if nobody is waiting for you.

Beyond accountability, solo runners often struggle with pacing. They tend to run their easy runs too fast and their hard runs too slow, landing in a "gray zone" of training that leads to burnout without the performance gains.

The Fix: Join a community! If you are a Denver local reach out to learn more about my training group that meets for weekly workouts and monthly long runs! If not, find a group in your area that you vibe well with.  There is a specific magic that happens when you’re surrounded by people chasing the same goal; the miles pass faster, the hills feel flatter, and the shared hard work forms bonds that make for fast friendships!

3. Treating Strength Training as "Optional"

If you only run to get better at running, you’re missing half the equation. Running is a series of single-leg hops. If your glutes, hips, and core aren't strong enough to stabilize your frame, your body will likely begin to breakdown with all the repetitive foot strikes.

The Fix: Incorporate two sessions of runner-specific strength training per week. You don’t need a powerlifting rig; focus on functional movements like squats, lunges, bridges, and planks. Strengthening your "chassis" ensures that when you hit mile 10 of your race, your form doesn't collapse.

4. Neglecting the "Fourth Discipline": Recovery

We don't actually get stronger while we're running; we get stronger in the hours and days after the run when our bodies repair the micro-tears in our muscles. Skipping rest days or skimping on sleep (aim for 7–9 hours!) is a fast track to overtraining syndrome.

If you aren't refueling with adequate carbohydrates and protein, your body will begin to break down muscle tissue to keep up with the demand.

The Fix: Treat your rest days with the same respect as your long runs. Use tools like foam rollers, prioritize high-quality nutrition, and listen to your body. If a "niggle" lasts more than three days, it’s a signal to back off before it becomes a full-blown injury.

Ready to Uplevel Your Running?

Training for a half marathon is a big commitment, but you don't have to do it alone. Whether you're a Denver local looking for the energy of in-person group runs or you're located anywhere else and want a customized training plan to hit a specific time goal, I'm here to help.

My coaching philosophy focuses on the whole runner—balancing miles with strength, recovery, and a supportive community. Let's make sure your next race is your best one yet.

Would you like me to send you a sample 4-week base-building schedule to get you started on the right foot?