Marathon training plan: 16 weeks to your first 42K
Running a marathon is a project of several months. This 16-week plan takes you from 16 km long runs to a 32 km one, with four runs a week, recovery weeks to absorb the work and a final taper so you reach the start line fresh.
Key takeaways
- Prerequisite: a half marathon or 30–40 km a week.
- The long run grows from 16 to 32 km, always at an easy pace.
- Take 30 to 60 g of carbohydrate per hour and test it first.
- Run the first 10 km a little slower than your goal pace.
Article contents
Are you ready for a marathon?
This plan assumes that, before week 1:
- You have finished a half marathon, or you run 30–40 km a week.
- You can run 14–16 km non-stop at an easy pace.
- You have been running regularly for at least 6 months, without injuries.
If you are not there yet, train for a half marathon first with our 12-week plan. It is the best step before 42K.
The four keys to marathon training
1. The long run
It grows from 16 to 32 km, always at an easy pace. It teaches your legs and body to handle three hours or more. You don’t need to run the full 42 km before race day.
2. Marathon pace
From week 5, sections at your goal pace appear. They check that your goal is realistic and make that pace feel natural on race day.
3. Threshold
“Comfortably hard” blocks raise the speed you can hold for a long time. They are demanding, but you should not finish exhausted.
4. Recovery
Every three or four weeks the volume drops. And the last three weeks taper off step by step so you arrive fresh. Skipping recovery weeks is one of the most common reasons runners arrive tired or injured.
16-week marathon training plan
Four runs a week. Keep at least one day between the quality session and the long run. Quality sessions include 2–3 easy kilometres at the start and 1–2 km at the end.
| Week | Easy | Quality | Easy | Long run | Total |
|---|---|---|---|---|---|
| 1 | 8 | 8: 8 × 1 min fartlek | 6 | 16 | 38 |
| 2 | 8 | 9: 5 × 1 km at 10K pace | 6 | 18 | 41 |
| 3 | 9 | 10: 2 × 15 min at threshold | 7 | 20 | 46 |
| 4 (recovery) | 7 | 8: 6 strides | 6 | 16 | 37 |
| 5 | 9 | 11: 6 km at marathon pace | 7 | 22 | 49 |
| 6 | 10 | 11: 3 × 12 min at threshold | 7 | 24 | 52 |
| 7 | 10 | 12: 8 km at marathon pace | 8 | 26 | 56 |
| 8 (recovery) | 8 | 9: 6 strides | 6 | 19 | 42 |
| 9 | 10 | 12: 6 × 1 km at 10K pace | 8 | 28 | 58 |
| 10 | 10 | 14: 10 km at marathon pace | 8 | 30 | 62 |
| 11 (recovery) | 10 | 12: 3 × 15 min at threshold | 8 | 24 | 54 |
| 12 | 10 | 14: 10 km at marathon pace | 8 | 30 | 62 |
| 13 | 10 | 12: 2 × 20 min at threshold | 8 | 32 | 62 |
| 14 | 9 | 12: 8 km at marathon pace | 7 | 24 | 52 |
| 15 | 8 | 10: 6 km at marathon pace | 6 | 16 | 40 |
| 16 (race) | 6 | 6: 4 strides | Rest | Marathon | — |
Eating and drinking during the marathon
In a race of more than two and a half hours, your glycogen stores are not enough. Sports nutrition guidelines recommend 30 to 60 g of carbohydrate per hour, and up to 90 g in very long efforts if your stomach is trained for it.
- Practise on long runs. Try your gels from the 20 km runs onwards.
- Start early: first gel around minute 40–45, then every 30–40 minutes.
- Drink to thirst at aid stations and add electrolytes in the heat.
- For the two days before, eat more carbohydrates (rice, pasta, bread, potatoes) and less fibre and fat.
Read more in our guide on what to eat before running.
Race-day strategy
The marathon rewards patience. Run the first 10 km a little slower than your goal pace. Settle into your pace until km 30. Use whatever you have left at the end.
To set your goal pace, use our pace calculator with your half marathon time. For a first marathon the estimate tends to be optimistic, so leave a few minutes of margin.
Looking for a marathon in Mexico? Check our race calendar.
Frequently asked questions
How long does it take to train for a marathon?
If you can already run a half marathon, 16 to 20 weeks. If you come from shorter distances, add several months of base training first.
How many kilometres a week should I run for a marathon?
Most first-marathon plans peak at 55–65 km in the heaviest weeks. What matters is building up gradually.
Do you need to run 42 km before race day?
No. A well-run 30 to 32 km long run is enough. Running further in training raises your injury risk.
What is hitting the wall in a marathon?
It is the sudden slump many runners feel around km 30, when glycogen runs out. Eating carbohydrates during the race and not starting too fast help prevent it.
We write practical training guides with the same logic the app uses: measure first, assume nothing.
This content is for information only and does not replace advice from a doctor or coach. If you have an injury or a heart condition, or have not exercised in a while, check with a professional before starting a plan.
