A marathon plan is not a 10K plan with extra miles bolted on. The long run is the centrepiece, medium-long runs and marathon-pace work carry the load, threshold sits alongside it as the second aerobic pillar, and VO2max moves to the background. The week is built around absorbing huge amounts of easy mileage while keeping one or two genuinely purposeful sessions.
Priority hierarchy (what to protect when life gets in the way):
For someone running 5–6 days/week, ~70–80% of running should be genuinely easy. Unlike a 10K block there is no dedicated VO2max day — quality is split between threshold and marathon pace (MP).
| Day | Session | Purpose |
|---|---|---|
| Mon | Rest / recovery | Absorb the long run + weekend |
| Tue | Medium-long easy (12–18 km) | Aerobic volume, time on legs |
| Wed | Quality — threshold or marathon pace | Aerobic strength + marathon-specific turnover |
| Thu | Easy / recovery | Volume + recovery |
| Fri | Medium-long easy (14–18 km) | Front-load endurance before the long run |
| Sat | Easy + strides | Recovery + neuromuscular speed |
| Sun | Long run (24–35 km) | The core marathon stimulus |
This is where a marathon is won. Weekly mileage gives you the ceiling, but the long run teaches your body — and your gut, your muscles, your nervous system — how to keep running when everything wants to quit. Most of it stays easy and conversational. As the plan matures, marathon-pace segments get embedded into it so it becomes a genuine race rehearsal.
Two long-run notes worth stealing:
Bookended between the easy days (Tuesday and Friday of a 6-day week), medium-long runs are the bridge between everyday volume and the long run. They let you accumulate 35–40% of your weekly volume without carrying the fatigue of a second long run. When you can't add kilometres anywhere else, add them here.
Don't audition for the marathon by training at every pace. Your goal pace has a specific feel — sustainable, controlled, a notch below threshold — and it needs to be practised. Give it a home on Wednesday:
These are aerobic workouts, not races. They make the specific fatigue from the long run's MP blocks feel familiar by race day.
Threshold work raises the speed you can sustain without the wheels coming off. Keep it controlled — RPE 7–8/10 — and rotate classic sessions:
In a marathon block, threshold plays supporting rather than starring role — it keeps the engine sharp while MP work and the long run do the heavy lifting.
The 10K plan has one. A marathon plan mostly doesn't — the volume is too high and the specific demand (sustain a steady effort for hours) is aerobic. VO2max work belongs in the background: if you're coming off a 10K or half block you've already banked it, and a few strides + the occasional surge cover enough of it during the build. Prioritise long run, volume, MP work and threshold first.
Strides stay year-round: 4–8 × 20 sec fast/relaxed with full easy recovery, once or twice a week (often after Saturday's easy run). They keep your neuromuscular system sharp without adding fatigue. The rest of the week is easy — actually easy — because the long runs and MP work only work if the other ~80% lets you recover.
A typical 16-week marathon build (shorter for low VDOT, longer for high) splits into five phases.
Build volume, keep the long run easy and progressive (10 → 21 km), and establish threshold work.
Long runs reach 24–30 km with a down week built in; MP work appears.
The business end — long runs get MP blocks and Wednesday becomes purely marathon-pace.
One last big week — 32 km with 3 × 5 km @ MP — then let the fitness settle in.
Marathon taper is longer than most. Volume falls week by week while you keep the engine lit: a short MP block two weeks out, then mostly easy runs, and a shakeout (+ a few strides) the day before.
Mileage, not cleverness, drives marathon results — but it has to fit your life and injury history.
Adjust volume before intensity. Protect the long run and the weekly total; let the MP and threshold sessions flex down when a week is compromised. The biggest principle: build a deep aerobic base with the long run and easy mileage, keep threshold as the engine, then make the last month genuinely marathon-specific.
Our marathon plan generator builds exactly this architecture — Sunday long run as the centrepiece, medium-long runs on Tuesday/Friday, threshold and marathon-pace quality on Wednesday, a 3-week taper, and marathon-pace blocks embedded in the long runs — personalized to your fitness and synced to your Garmin watch.
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