Sub-4 Marathon: Paces, Training and Race Strategy
A sub-4 marathon is the big goal for many recreational runners. It means holding 5:41 per kilometre for 42.195 kilometres, and the key is reaching the end with enough energy to sustain that pace. This guide explains which time makes it realistic, what paces and volume you need, the key sessions and how to approach the race.
When a sub-4 marathon is realistic
The most useful reference is your half marathon. The Riegel formula says a 1:54 half equals a 4-hour marathon, but a study by Vickers and Vertosick of 2,303 recreational runners found that the formula works well up to the half marathon and greatly underestimates marathon time: for half of the runners it gave times at least 10 minutes faster than their real ones.
In practice, to break 4 hours with some margin you want a recent half marathon of 1:50 to 1:52 or better. You can run your numbers with the race time predictor, bearing in mind it tends to be optimistic for the marathon.
The same study found that weekly volume and interval training were linked to higher speed at every distance. Running enough kilometres matters.
Your paces for a sub-4 marathon
| Session type | Approximate pace |
|---|---|
| Easy run and long run | 6:20 to 6:50 /km |
| Marathon pace | 5:35 to 5:40 /km |
| Threshold or tempo | 5:10 to 5:15 /km |
| Short intervals | 4:45 to 4:55 /km |
To fine-tune them from your current time, use the training pace calculator.
How to train for a sub-4 marathon
Volume and duration
A 14- to 16-week build, with 4 or 5 training days and volume reaching 50-60 kilometres a week in the heaviest weeks, is a common base for this goal. There is a full week-by-week plan in the marathon training plan.
Main sessions
- Long run: build gradually to 28-32 kilometres at an easy pace. I explain how in the guide to the long run.
- Marathon pace blocks: for example, 2 × 6 km at 5:38 within a run, or the last 8-10 km of a long run at that pace.
- Threshold: 20 to 30 minutes at threshold pace, continuous or in blocks. There are examples in the guide to threshold training.
- Strength: two sessions a week to handle the volume.
Train your race fuelling
In a 4-hour marathon you need to take in carbs during the race. Practise with gels or sports drink on your long runs so your stomach gets used to it; I explain it in the guide to training your gut. The race carb calculator helps you work out how much.
How to race a sub-4 marathon
- Carb load in the days before. There is more in the guide to carb loading.
- Start 5 to 10 seconds per kilometre slower for the first few kilometres and settle into goal pace afterwards. If you start fast, the risk of hitting the wall at kilometre 30 shoots up. I explain the strategy in the guide to the negative split.
- If you run with a 3:59 or 3:55 pacer, do not glue yourself to them at the start or at aid stations.
- Take carbs from the start, every 30-40 minutes, even if you are not hungry.
- Everything is decided between kilometre 30 and 42. If you started calmly, this is where you will pass a lot of people.
Conclusion
A sub-4 marathon requires 5:41 per kilometre. It is realistic with a recent half marathon of 1:50 to 1:52, because the Riegel formula tends to be optimistic for the marathon. Prepare over 14 to 16 weeks with long runs up to 30 kilometres, marathon pace blocks, threshold work and strength. Practise your race fuelling and start calmly.
FAQ
What pace do you need for a sub-4 marathon?
An average of 5:41 per kilometre. Many runners aim for 5:35-5:38 to build in a margin.
What half marathon time do I need for a sub-4 marathon?
A recent half of 1:50 to 1:52 or better gives a reasonable margin. The Riegel formula says 1:54, but it often falls short for the marathon.
How many kilometres a week should you run?
In the heaviest weeks, 50 to 60 kilometres is a common reference.
How long should the longest run be?
Between 28 and 32 kilometres, at an easy pace, three or four weeks before the race.
How many gels should you take in a 4-hour marathon?
It depends on the grams per gel and your tolerance. The race carb calculator helps you work it out.
