Miles with Misty Coaching

The “10% Rule” Might Need a Smarter Update!

Most runners have heard the classic rule: “Do not increase your weekly mileage by more than 10%.”

But newer research suggests we may need to look more closely at single-run spikes, not just weekly mileage.

A large 2025 cohort study followed 5,205 adult runners over 18 months and analyzed 588,071 running sessions using Garmin data. The researchers found that injury risk increased when the distance of a single run was more than 10% longer than the runner’s longest run in the previous 30 days.

That means the risky part may not always be your total weekly mileage. It may be the one run that suddenly jumps too far beyond what your body has recently handled.

In the study, runners had a higher rate of overuse injury when they had:

A small spike of more than 10% to 30%: HRR = 1.64
A moderate spike of more than 30% to 100%: HRR = 1.52
A large spike of more than 100%: HRR = 2.28

The researchers did not find the same clear relationship with simple week-to-week mileage changes, which makes this especially important for runners training for longer distances.

My takeaway:
Before adding a big long run, look back at your longest run from the past 30 days. Your next long run should usually stay within about 10% of that distance, especially if you are newer, returning from injury, building for a marathon, or feeling run down.

For example:

If your longest run in the last 30 days was 8 miles, a smart next long run would be around 8.5 to 9 miles, not 11 or 12.

Progression matters. Consistency matters. Your body adapts best when you give it enough stress to grow, but not so much that it breaks down.

For full research article:
https://doi.org/10.1136/bjsports-2024-109380

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When most people think about fitness, they often think about weight loss, building muscle, or improving endurance. But movement is so much more than that.

How Movement Supports Mental Health - Miles With Misty Coaching When most people think about fitness, they often think about weight loss, building muscle, or improving endurance. But movement is so much more than that. At Miles with Misty Coaching, I believe fitness should support the whole person — body, mind, confidence, energy, and daily life. Exercise is n...

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Boston Marathon finisher!!! !

Congrats on running the Boston Marathon yesterday, Tina!!!! I'm so incredibly proud of you and all of the work you put in leading up to this day. You showed so much commitment and determination this entire training cycle. Even with some massive setbacks, I never doubted for a second that you would tackle this goal of yours and finish this incredible race.

You remained focused, continued to show up for your runs, and trusted in the process. That finisher's medal was soooo well deserved and this achievement will forever be something that no one can take from you.

You Rock, Tina! Boston loves you!
https://www.facebook.com/share/p/1C8S7hHJxQ/

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Congratulations to our Winter Warrior Beginner 5K Runners!
Through the cold, the warm days, the few perfect ones, and even a rainy race day, you stayed committed and kept showing up.
You trusted the process, stayed the course, and crossed the finish line of the Ringing in Spring 5K together.
So proud of all of you! Your hard work, grit, and determination paid off! 💪🏃‍♀️🌧️✨ Check out more pictures here: https://drive.google.com/drive/folders/1v9Q_clWqSplmh9lCvO-YkSrSsdVrtZQs?usp=sharing

Ever wonder why some runs feel smooth while others feel like a struggle?

A big factor could be hemoglobin.

Hemoglobin is the protein in red blood cells that carries oxygen from your lungs to your muscles. During aerobic exercise like running, your muscles rely on that oxygen to produce energy.

When hemoglobin levels are low, oxygen delivery drops. That can make your usual pace feel harder, raise your heart rate, and increase fatigue.

This is why runners should pay attention to recovery, fueling, and iron intake, especially endurance athletes and women who are at higher risk of iron deficiency.

Healthy training builds endurance, but it also supports better oxygen delivery throughout the body.

Train smart. Fuel well. Recover well.

Every run teaches you something. How your breath feels today, how your legs respond, what pace feels honest.

Instead of fearing a “bad run,” get curious about what’s actually happening. Curiosity keeps you calm, present, and open to growth. Fear shuts the door.

Notice one thing today: your cadence, your breath, or how the first mile settles. That’s your win.