16-Week Marathon Training
The standard marathon build: phases, long runs and taper over 16 weeks.
- Written by
- YourMarathonPace
- Published
- 9 November 2026
This guide is general information, not medical or coaching advice. It has not yet been reviewed by a qualified coach. Speak to a doctor before starting a new training programme, especially if you have a health condition or injury.
Why 16 weeks is standard
Sixteen weeks gives enough time to build endurance gradually, absorb a few hard weeks and still allow for a missed week through illness or life. It suits most runners who can already run regularly for 30–45 minutes.
Base, build and peak phases
A typical structure is around six weeks of base running (mostly easy mileage and a growing long run), six weeks of build (adding marathon-pace and threshold work) and a peak block before the taper. Most training in successful endurance programmes is done at low intensity, with a smaller share of hard work.
Long-run progression
Long runs usually increase by about a mile (1–2 km) most weeks, with a shorter long run every few weeks to recover. Many plans peak at 18–22 miles (29–35 km). Running some of the later long runs partly at goal pace helps you rehearse pacing and fuelling.
Taper
Most plans cut weekly mileage over the final two to three weeks while keeping a little running at goal pace, so your legs stay sharp. Expect to feel restless or sluggish during the taper. That's normal, and it isn't a sign you've lost fitness. Don't try to make up missed sessions in race week.
Sources
- What is best practice for training intensity and duration distribution in endurance athletes? — International Journal of Sports Physiology and Performance (Seiler, 2010)
- The training–injury prevention paradox: should athletes be training smarter and harder? — British Journal of Sports Medicine (Gabbett, 2016)
This guide is general information, not medical or coaching advice. It has not yet been reviewed by a qualified coach. Speak to a doctor before starting a new training programme, especially if you have a health condition or injury.