Running Mileage Progression Calculator

Frequently Asked Questions

• What is a mileage progression plan?

  A structured schedule showing how to increase weekly mileage from a starting point to a target over a set number of weeks, including planned cutback weeks for recovery.

• How many weeks does it take to reach a mileage goal?

  At 10% increase per week with cutback weeks every 4th week, doubling mileage takes ~12 weeks. Reaching 50 miles/week from 25 takes 10–14 weeks safely.

• What is a cutback week in a progression plan?

  Every 3–4 weeks, reduce mileage by 20–30% from the previous build week peak. This allows recovery and adaptation before the next build phase. Never skip planned cutbacks.

• Should my progression plan include taper weeks?

  If training for a race, include a 1–3 week taper at the end (reducing mileage 20–40%). Add taper weeks after your peak mileage, before the race.

• What mileage is needed for a half marathon?

  Most half marathon plans peak at 35–45 miles/week (56–72 km). For first-timers, 25–35 miles/week is sufficient. Build to peak mileage 3–4 weeks before race day.

• What mileage is needed for a full marathon?

  Most plans peak at 50–70 miles/week (80–113 km). First-time marathoners may peak at 40–50 miles/week. Some sub-elite runners reach 80–100 miles/week.

• What is base building?

  Base building is increasing aerobic mileage before adding speed work. Typically 8–16 weeks of gradual mileage increase at easy effort (conversational pace). Builds aerobic foundation.

• Can I follow a progression plan after injury?

  Return to 50–60% of pre-injury mileage, then rebuild from there. Don't start from 0 if you maintained some fitness. Progress more conservatively (5–7% per week) when returning from injury.

• How do I adjust if I miss a week?

  Step back to previous week's mileage (don't advance). After missing 2+ weeks, return at 50–60% of where you left off. Resume progression from the stepped-back point.

• What if I hit my target mileage before the plan ends?

  Maintain the target for 2–4 weeks with cutback weeks before adding more. Consolidation (running consistently at a level) is as important as increasing.

• Should long runs increase proportionally?

  Long run should be 25–35% of weekly total. If weekly mileage is 40 miles, long run = 10–14 miles. Increase long run every other week, not every week.

• How does progression differ for 5K vs marathon training?

  5K: lower peak mileage (20–40 miles/week), more speed work. Half marathon: moderate peak (35–50). Marathon: highest peak (45–70+). All require gradual progression.