First marathon: the plan for your level
You can't negotiate with 42.195 km — but you can prepare for it very well, provided you start from YOUR real level, not the level of some PDF plan found online. Here's how Greg sizes a first marathon build: duration first, ambition second.
How many weeks? The honest answer
| Your current level | Preparation time | Sessions / week | Realistic goal |
|---|---|---|---|
| Running for less than 6 months, never past 10 km | 20 to 24 weeks | 3 then 4 | Finish — and finish well |
| Regular runner, one half-marathon done | 16 weeks | 4 | Finish comfortably (4:00–4:30 depending on profile) |
| 30-45 km/week for months, several races | 12 to 14 weeks | 4 to 5 | A target time (validated by Greg from your data) |
Greg's rule: for a FIRST marathon, goal #1 is finishing in good shape. The clock is for your second one.
💬 The plan is the foundation. Chatting with Greg is the secret weapon.
Four months of preparation means four months of questions: tight calf, overloaded week, pre-race doubt. UpGreg's edge: your coach answers at any hour, with your data in front of him — and recalibrates the plan on the spot.
Excerpt of a typical conversation with Greg in the app
The 3 phases of the plan
- Base (40-50% of the plan): progressive aerobic volume, strength work twice a week, the long run grows in 30-minute steps. This is where the last 10 kilometers of race day are won.
- Specific: long runs up to 30-32 km (never 42 in training — it only brings damage), marathon-pace blocks, fueling tested in real conditions.
- Taper (2-3 weeks): volume melts, intensity stays, freshness returns. The part everyone sabotages by trying to “catch up” on missed sessions.
Sample week (16-week build, mid-plan)
- Tuesday — 45-min easy run + strides
- Thursday — quality session: 2 × 20 min at marathon pace, 5-min recovery
- Saturday — 40-min very easy run (or rest if fatigue builds up)
- Sunday — progressive long run: from 1 h 30 to 2 h 45 across the plan
The mistakes that cost a first marathon
- Chasing a time on your first — the distance IS the goal.
- Running long runs too fast: they should be 45-60 s/km slower than your target marathon pace.
- Skipping strength work: it's what keeps your hips upright at km 35.
- Innovating on race day — shoes, gels, breakfast: everything gets tested in training, nothing gets discovered in the race.
Frequently asked questions
Can you prepare a first marathon in 12 weeks?
Only if you're already running at least 30 km a week and have been for months. Below that, 16 to 24 weeks protect your tendons and make the experience enjoyable — which is the point.
What's the longest run before race day?
30 to 32 km, three weeks before the race. Running 42 km in training fatigues more than it prepares: the final kilometers are earned through the plan's accumulation, not a dress rehearsal.
Are 3 sessions a week enough?
To finish, yes — provided they're well built (one quality session, one easy run, one long run). 4 sessions make the build more comfortable and safer.
Is walking during the marathon a failure?
Not at all: walking through aid stations is a strategy even experienced runners use. A first marathon finished with some walking beats a DNF at km 32.
Is there a plan for a half marathon or a 10K too?
This page covers the marathon, but the same principle applies to shorter distances: a half marathon builds in 8 to 12 weeks, a 10K in 6 to 10 weeks, with noticeably lower volume. Just tell Greg your distance in the chat — he adjusts the plan accordingly.
« A first marathon deserves respect: I look at your actual last 28 days before proposing a preparation length — not your memories of the athlete you were five years ago. And if you ask me for a marathon in 8 weeks while running twice a month, I'll say no. That's what a coach is for, too. »
Understanding AI sports coaching →
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