How it works
VDOT (from your recent race) → training paces → periodised volume ramp with cutback weeks and a taper.
First we compute your VDOT from the recent race using the Daniels–Gilbert model (the same maths behind the race-time predictor). VDOT sets your easy, marathon, threshold, and interval paces. The plan then splits the weeks into four phases — Base, Build, Peak, and a 2–3 week Taper (3 weeks for plans of 12 weeks or more), each with its own focus and signature key workout. Base phase: aerobic mileage — easy aerobic running at E pace plus 6×20 s strides twice a week. Build phase: threshold and tempo — 4–5×6 min or 20 min steady at T (threshold) pace. Peak phase: VO2max and race pace — VO2max intervals of 5–6×3 min at I pace, plus a long run with a marathon-pace finish. Taper phase: sharpen and rest — short reps with brief touches at I–M pace and low volume. Weekly volume starts conservatively and ramps roughly 8–10% per week, following the long-standing ACSM guidance to increase training load by no more than about 10% weekly. Every fourth week is a cutback (recovery) week, where volume steps back about 18% so the body absorbs the work and you avoid the overuse injuries that come from ramping without rest. The long run grows as a capped fraction (~30%) of weekly volume — never more than about 35 km (22 mi) — peaks before the taper, then drops so your legs are fresh on race day. A typical marathon plan runs 16–20 weeks (12 for experienced runners with a solid base, up to 24 for first-timers), and the marathon pace calculator plus Yasso 800 calculator help you nail the goal-pace and interval targets the Peak phase is built around.
Sources
- Daniels — phases, paces and periodisation Jack Daniels, “Daniels' Running Formula,” 3rd ed., Human Kinetics (2014). Source for the Base/Build/Peak/Taper structure and the E/M/T/I training paces derived from VDOT.
- ACSM — progression of training load American College of Sports Medicine, “ACSM’s Guidelines for Exercise Testing and Prescription,” 11th ed. (2021). Basis for the conservative ~10%-per-week volume progression and recovery (cutback) weeks.
- Daniels–Gilbert VDOT model Jack Daniels & Jimmy Gilbert, “Oxygen Power: Performance Tables for Distance Runners” (1979) — the VDOT that seeds this plan.
- Hal Higdon — marathon plan length & weekly mileage norms Hal Higdon, “Marathon Training Programs” (halhigdon.com): Novice plans run 18 weeks and peak around 30–40 mi/week; intermediate/advanced plans build to roughly 40–55+ mi/week. Source for the population norms on typical plan length and peak weekly mileage (not the runner’s own VDOT-scaled volume, which the calculator computes).
- Boston Athletic Association — marathon training guidance Boston Athletic Association, “Boston Marathon Training” (baa.org). Corroborates the conventional 16–20-week build for typical marathoners and a long run building toward ~20 miles.
FAQ
How many weeks is a marathon training plan?
A typical marathon plan runs 16–20 weeks. Experienced runners with an established aerobic base can prepare in about 12 weeks, while first-timers — or anyone building from a low base — often benefit from 18–24 weeks so mileage can ramp gradually. This calculator adapts to whatever window you have: enter your weeks until race day and the plan compresses or expands its Base, Build, Peak, and Taper phases to fit, always ending on a 2–3 week taper.
How many miles per week do I need to train for a marathon?
As a population guide, beginner marathon plans peak around 30–40 miles (50–65 km) per week, intermediate plans around 40–55 miles (65–90 km), with the long run building toward roughly 20 miles (32 km). Your own numbers are personalised, though: this calculator scales the starting volume to your goal distance and VDOT fitness, ramps about 8–10% per week, and caps the long run at ~30% of weekly volume (and ~35 km / 22 mi). Read your individual peak weekly volume and peak long run straight off the result — they will not necessarily match the generic ranges above.
How is the plan built?
Your recent race gives a VDOT fitness score, which sets your training paces. The weeks are then divided into Base, Build, Peak, and Taper phases. Weekly volume ramps about 8–10% per week with a cutback week roughly every fourth week, and the long run grows to a capped fraction of weekly volume before the taper trims everything back for race day.
Is this a substitute for a real coach?
No. It is a structured starting template based on well-established periodisation principles, not personalised coaching. A coach adjusts for your history, injuries, life stress, and how each week actually felt. Use this plan as scaffolding and listen to your body — skip or shorten sessions when you are run down.
What if I have fewer weeks than a typical plan?
The plan compresses gracefully. Short plans (under about six weeks) still finish with a 1–2 week taper and spend their limited time on the most race-specific work; very short plans skip the earlier base phase. You simply get less aerobic build-up, so keep expectations modest and prioritise consistency over big jumps in mileage.
How are the training paces chosen?
They come from your VDOT via Jack Daniels’ tables: an easy range, marathon pace, threshold (tempo) pace, and interval (VO2max) pace. The key workout for each week references the pace appropriate to its phase — easy in Base, threshold in Build, intervals and marathon pace in Peak, short sharpeners in the Taper.
Why are there cutback weeks?
Fitness is built during recovery, not during the hard weeks themselves. A cutback week (about 18% less volume) every fourth week lets your body adapt to the preceding load, reduces cumulative fatigue, and lowers injury risk. Skipping recovery is one of the most common ways self-coached runners get hurt.
Are the weeks dated to my race day?
Yes. Enter your goal race day and the plan dates every week back from it: the final week is race week, and each earlier week starts seven days before the next. The “Week of” column shows the calendar date each training week begins, so you can map the plan straight onto your calendar.
Can I download the plan or add it to my calendar?
Not as a one-click .ics or PDF export yet — that is planned design work. For now the plan is fully printable: use your browser’s print (or “Save as PDF”) to keep a copy or share it.
General fitness information, not medical or coaching advice. Volume figures are estimates — build mileage conservatively, prioritise recovery, and back off at the first sign of injury. Consult a qualified coach or clinician for a personalised plan, especially if you are new to running or returning from injury.