Free Running Mileage Progression Calculator

How to Safe Build Weekly Running Volume

The most common mistake in distance running isn’t running too slow—it’s building volume too fast. As coaches, we know that consistency trumps intensity, especially during the base phase. However, manually calculating a safe, linear progression for an entire roster of athletes is a spreadsheet nightmare.

I built this Mileage Progression Calculator to solve two specific problems:

  1. Eliminating “Math Fatigue”: It instantly calculates a 12-week build based on the “10% Rule,” saving you hours of planning time.
  2. Enforcing Recovery: Most athletes (and many coaches) forget to schedule down weeks. This tool automatically inserts a “cutback” week every fourth week to allow the body to absorb the training load before the next jump in volume.

Whether you prefer tracking by Total Weekly Miles or Minutes Run, this tool provides a clear, day-by-day roadmap to safely increase capacity without risking injury.

Mileage Progression Calculator

Week Type Total Mon
(12%)		 Tue
(20%)		 Wed
(12.5%)		 Thu
(12.5%)		 Fri
(12%)		 Sat
(25%)		 Sun

The Logic Behind the Calculator

This tool uses a 3-Up, 1-Down Linear Periodization model. Here is exactly how the math works:

1. The Macro Structure (The 10% Rule)

  • Build Weeks (Weeks 1-3): The total volume increases by 10% each week. This creates a progressive overload stimulus.
  • Cutback Week (Week 4): Every fourth week, volume drops by 10% relative to the previous peak. This reduction reduces cumulative fatigue and lowers cortisol levels, allowing for “supercompensation” (fitness adaptation).
  • Resumption (Week 5): This is the smart part of the calculator. Instead of building off the low volume of the cutback week, the calculator looks back to Week 3 (your previous peak), adds 10%, and resumes the build from there. This ensures you don’t lose momentum.

2. The Daily Split (Microcycle)

The weekly volume is distributed to prioritize quality work on specific days while ensuring recovery on others. The percentages correspond to a standard high school or collegiate training week:

  • Monday (12%): Easy / Shakeout run.
  • Tuesday (20%): Workout Day (e.g., Threshold, Hills, CV Intervals).
  • Wednesday (12.5%): Medium-long recovery run.
  • Thursday (12.5%): Maintenance run.
  • Friday (12%): Easy run.
  • Saturday (25%): Long Run. The anchor of the week.
  • Sunday (Rest): Full recovery.

About the Coach

Coach Saltmarsh specializes in high school distance running and athlete development. With a focus on data-driven training and consistent progression, this site provides the tools and insights coaches and athletes need to reach their peak performance. This calculator was built to solve a common problem on the track: making running math simple, so you can focus on the splits that matter.

Looking for more training resources? Explore the Training Articles or view Coaching Resources.