What pace is a sub-4 marathon?

9:09 per mile, or 5:41 per kilometre. In practice you want to be able to hold 9:00 comfortably in training so 9:09 on race day has some room in it.

What half marathon time equals a sub-4 marathon?

Roughly 1:53, assuming you have marathon-specific endurance. A 1:53 half off a well-built block predicts about 3:57. Off low mileage it predicts optimistically, which is the usual trap.

How many miles a week to break 4 hours?

It is done on 30. It is comfortable on 40 to 45. The extra mileage does not make you faster over 10K, it makes the last 10K of the marathon a different experience.

How long does it take to go from finishing a marathon to sub-4?

One well-built block if you finished around 4:15 to 4:30. Two if you finished over 4:45. The jump is mostly aerobic volume, and volume takes time to absorb safely.

Train for

Breaking 4 hours in the marathon

Four hours is the first marathon barrier that means something. It is 9:09 per mile, or 5:41 per kilometre, held for 26.2 miles, and the gap between finishing a marathon and breaking four is bigger than it looks.

The pace

Split	Time	Per mile	Per km
10K	56:50	9:09	5:41
Half	1:59:50	9:09	5:41
30K	2:50:30	9:09	5:41
Marathon	3:59:50	9:09	5:41

Are you close?

Sub-4 asks for roughly a 1:53 half marathon or a 51 minute 10K on the same fitness. If you are near those, the marathon time is a training problem. If you are a long way off, it is a fitness problem first.

Half marathon around 1:53. You have the speed. The block is about endurance and pacing discipline.
10K around 51:00. Same story. Sub-4 is well within reach on 35 to 45 miles a week.
Half marathon over 2:05. Chasing sub-4 off this is how people blow up at 30K. Build for a season, come back to it.

The mileage that makes it comfortable

You can break four hours off 30 miles a week. It will be uncomfortable and the last 10K will be a fight. Peaking at 40 to 45 miles a week turns sub-4 from a maximal effort into a controlled one, which matters because a marathon run at the edge of your fitness punishes every small error.

Structure the week as four to five runs. Most of them easy at 10:30 to 11:30 per mile, which will feel absurdly slow relative to 9:09 and is exactly the point. One threshold session, one long run, and marathon-pace work folded into the long run from week six.

The sessions that build it

Marathon pace in the long run. The signature session. Build from 4 miles at 9:09 inside a 14 mile run to 10 miles at 9:09 inside an 18 mile run. If you can do the latter comfortably three weeks out, you are ready.
Threshold. 20 to 40 minutes at roughly 8:30 per mile, either continuous or as 2 x 15 minutes. Raises the ceiling that marathon pace sits under.
Long run progression. 13, 15, 13, 16, 18, 15, 18, 20. Up three, back one. The down weeks are not optional.

Where sub-4 attempts go wrong

Almost always at 30K, and almost always because of something done in the first 10K. Nine minute miles feel easy at mile 3 when you are fresh and the crowd is loud, and a 20 second per mile cushion banked early costs about four times that at the end.

The other failure is fuelling. Four hours is long enough that you cannot run it on what you started with. Carbohydrate every 30 to 40 minutes from the first hour, not from when you feel empty, because by then it is 20 minutes too late.

Frequently asked

What pace is a sub-4 marathon?: 9:09 per mile, or 5:41 per kilometre. In practice you want to be able to hold 9:00 comfortably in training so 9:09 on race day has some room in it.
What half marathon time equals a sub-4 marathon?: Roughly 1:53, assuming you have marathon-specific endurance. A 1:53 half off a well-built block predicts about 3:57. Off low mileage it predicts optimistically, which is the usual trap.
How many miles a week to break 4 hours?: It is done on 30. It is comfortable on 40 to 45. The extra mileage does not make you faster over 10K, it makes the last 10K of the marathon a different experience.
How long does it take to go from finishing a marathon to sub-4?: One well-built block if you finished around 4:15 to 4:30. Two if you finished over 4:45. The jump is mostly aerobic volume, and volume takes time to absorb safely.

Your block, written

Put a date on it and Shed builds the weeks.

Shed takes your goal, your race date, and the days you can actually run, then writes every session between here and the start line. It reads each run off your Apple Watch the same day and moves what needs moving. No spreadsheet, no guessing at paces.

Get your plan on iPhone