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Tool No. 06

Mileage
Ramp Tracker

Enter your current weekly mileage and target. Get a week-by-week build plan that respects the 10% rule and helps you avoid the most common cause of running injuries.

Your Mileage
Your average over the last 3–4 weeks. If last week was an outlier, use the week before it.
The peak week mileage you want to reach before tapering for your goal race.
The standard 10% rule — increase no more than 10% per week. Safe for most trained runners.
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Enter your mileage
to generate your schedule

Week-by-Week Schedule
How It Works
The 10% Rule,
And When to Break It

The 10% rule — never increase weekly mileage by more than 10% in a single week — is the most widely cited injury-prevention guideline in running. The research behind it is real: rapid mileage spikes are consistently the leading cause of overuse injuries like stress fractures, IT band syndrome, and plantar fasciitis.

This calculator applies the 10% rule with one important addition: a cutback week every fourth week at 80% of your previous volume. This is where adaptation actually happens. The body doesn't get stronger during the training — it gets stronger during the recovery from it.

The 8% option is appropriate for injury-prone runners or those returning from a break. The 12% option is only for experienced runners with a strong base who are intentionally accelerating a build — and even then, the cutback weeks aren't optional.

Common Questions

How many miles per week should I run for a half marathon?

A solid half marathon training peak is 30–45 miles per week for most intermediate runners. Beginners can finish on 20–25 miles per week. Going higher than 50 miles per week for a half is usually unnecessary and increases injury risk without proportional benefit unless you're chasing a significant PR.

What is a cutback week in running training?

A cutback week is a planned reduction in mileage — typically to 70–80% of your previous week — built into your training every 3–4 weeks. It's not a rest week. You still run, but at lower volume to let your body absorb the preceding weeks of training load. Skipping cutback weeks is one of the fastest routes to overtraining.

What happens if I miss a week of training?

Repeat the week you missed rather than skipping ahead. One missed week won't meaningfully hurt your fitness — trying to make up for it by jumping to higher mileage will. Aerobic fitness is lost slowly; injury risk from a sudden spike is immediate.

How long does it take to safely increase mileage?

Going from 20 to 40 miles per week safely takes roughly 10–14 weeks following the 10% rule with proper cutbacks. Rushing this is the single most common mistake in amateur marathon and half marathon training. Your cardiovascular system adapts faster than your connective tissue — bones, tendons, and ligaments need the full build time.

Is the 10% rule scientifically proven?

The specific 10% figure is a rule of thumb, not a rigid scientific law — some studies suggest the cutoff is closer to 20–30% before injury risk spikes significantly. But the underlying principle is well-supported: rapid mileage increases correlate strongly with injury. The 10% rule is a conservative, practical implementation of that principle.
Field Note
Decoding Running Paces — the six training paces every serious runner should understand and when to use each one.
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