12-week half marathon training plan — advanced
A free 12-week half marathon plan for advanced runners: 5 runs a week, peaking at 55 km, with cutback weeks and a real taper.
| Week | Phase | Sessions | Long run | Total |
|---|---|---|---|---|
| Week 1 | base |
| Long run10km | Total26km |
| Week 2 | base |
| Long run12km | Total28km |
| Week 3 | base |
| Long run14km | Total34km |
| Week 4 | cutback |
| Long run10km | Total26km |
| Week 5 | build |
| Long run16km | Total39km |
| Week 6 | build |
| Long run19km | Total47km |
| Week 7 | build |
| Long run21km | Total49km |
| Week 8 | cutback |
| Long run15km | Total37km |
| Week 9 | peak |
| Long run23km | Total55km |
| Week 10 | taper |
| Long run15km | Total37km |
| Week 11 | taper |
| Long run10km | Total26km |
| Week 12 | race |
| Long run21.1km | Total29.1km |
Who this plan is for
This is the advanced version — it assumes an established base and a specific goal, with two quality sessions a week. It runs 12 weeks, 5 days a week, and peaks at 55 km in the hardest week.
If that sounds like too much or too little, the same half marathon block exists at other levels and lengths — the related plans below are the same engine with different inputs.
How the plan is built
Cutback weeks. Roughly every fourth week drops to about 70% of the previous long run. Adaptation happens during the easier week, not the hard one.
Progression is capped at 20%. No week's long run climbs more than a fifth above the last progressive week. Where a shorter plan cannot reach the usual peak inside that limit, it arrives at a lower peak rather than taking an unsafe step.
A real taper. The closing weeks come down hard, and race week carries almost nothing — two short shakeouts totalling 8 km before the start line.
This plan, but it adapts
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Fair questions
How many miles a week is this half marathon plan?
It peaks at 55 km (about 34 miles) in the hardest week, and totals roughly 433 km across the 12 weeks.
What is the longest run in a 12-week half marathon plan?
23 km. Long runs exceed race distance at this event because the limiter is aerobic base, not distance.
Is 12 weeks long enough to train for a half marathon?
For a advanced runner, yes — provided you are starting from the base this plan assumes. If you are not, the longer version of this plan is the more forgiving choice, mainly because it absorbs missed weeks better.
Is this plan free?
Yes. Every week is on this page. The subscription is for the app, which adapts the plan around the sessions you actually complete.