Race Training Plan Generator

This race training plan generator turns three numbers — your current weekly mileage, your target race distance, and how many weeks you have left — into a week-by-week mileage table you can actually follow. It doesn't invent an arbitrary ramp: every week is built from two real, widely-published training principles applied together, the same way structured coaching plans are put together, and it runs entirely in your browser with nothing uploaded anywhere.

The first principle is the "10% rule": a long-standing, widely-repeated guideline in running and sports-medicine circles that raising total weekly mileage by more than about 10% from one week to the next meaningfully raises injury risk, because tendons, bones and connective tissue adapt more slowly than cardiovascular fitness does. This tool enforces that cap literally — no single build week in the table is ever more than 10% above the highest mileage you've reached so far in the plan.

The second principle is a step-back (cutback) periodization pattern: three weeks of building mileage followed by one deliberately lighter "recovery" week at roughly 75% of the peak you just reached, then the cycle repeats. This is the same load/unload rhythm used by popular structured plans (Hal Higdon-style schedules are a well-known example) to let the body absorb training before pushing further. In the final one to three weeks before race day — scaled to both your race distance and how long your plan is — the tool tapers mileage down instead of building it, dropping to roughly 30-50% of peak in race week so you arrive rested rather than fatigued.

The peak weekly mileage the plan builds toward is general, commonly-cited guidance blended with your own current mileage — not a personalized coaching prescription, and it doesn't know your injury history, age or health status. If the weeks you have left simply aren't enough to reach a safe mileage base for your chosen distance even under a best-case 10%-per-week build, the tool says so plainly instead of drawing an unsafe chart — the honest move is a shorter-distance goal or a longer runway, not a fabricated plan. Treat the table as a sensible starting structure, adjust it around how your body actually responds, and check with a coach or doctor if you have any injury history or medical concerns.