A 12-week plan to break four hours
Five runs a week, two of them with a job to do, and a pace for every session. Built for runners who have finished a marathon or a strong half and want the clock to start with a three.
Are you ready for sub-4?
A 3:59 marathon is 5:41 per kilometre for 42.2 km. Before you start this plan, you should be able to run 10 km in about 53 minutes or a half marathon in about 1:55, and you should already run four or five times a week for 35 to 45 km. Those are the numbers that predict a sub-4 marathon after twelve focused weeks.
If your recent 10 km is closer to 58 minutes, follow the 16-week plan first, or aim for 4:15 and let the next race take the four hours.
Your training paces
- Easy
- 6:20 to 6:50. Conversational. If your heart rate drifts up in heat, slow down further.
- Long run
- 6:10 to 6:40, with the fast-finish sections at marathon pace.
- Marathon pace
- 5:35 to 5:40. The single most important pace in the plan.
- Tempo
- 5:15 to 5:20, about half marathon effort.
- Intervals
- 4:55 to 5:05, about 10 km to 5 km effort, with 2 minutes of easy jogging between reps.
The plan, week by week
| Week | Tue | Wed | Thu | Sat | Sun | Total |
|---|---|---|---|---|---|---|
| 1Build | Intervals10 km · 6×800 m | Easy8 km | Tempo10 km · 3×8 min | Easy6 km | Long run18 km | 52 |
| 2Build | Intervals11 km · 5×1 km | Easy8 km | Marathon pace11 km · 2×4 km | Easy7 km | Long run21 km | 58 |
| 3Build | Intervals11 km · 6×1 km | Easy9 km | Tempo12 km · 2×15 min | Easy7 km | Long, fast finish24 km · +6 km | 63 |
| 4Deload | Easy + strides8 km · 6×20 s | Easy7 km | Tempo9 km · 2×10 min | Easy5 km | Long run16 km | 45 |
| 5Build | Intervals12 km · 4×1600 m | Easy9 km | Marathon pace13 km · 2×5 km | Easy8 km | Long run26 km | 68 |
| 6Build | Intervals12 km · 6×1 km | Easy10 km | Tempo13 km · 3×12 min | Easy8 km | Long, fast finish28 km · +8 km | 71 |
| 7Build | Intervals13 km · 5×1600 m | Easy10 km | Marathon pace15 km · 10 km | Easy8 km | Long run30 km | 76 |
| 8Deload | Easy + strides8 km · 6×20 s | Easy8 km | Tempo10 km · 2×12 min | Easy6 km | Long run20 km | 52 |
| 9Peak | Intervals13 km · 6×1 km | Easy10 km | Marathon pace16 km · 12 km | Easy8 km | Long, fast finish32 km · +10 km | 79 |
| 10Peak | Intervals12 km · 5×1 km | Easy9 km | Marathon pace14 km · 2×5 km | Easy7 km | Long run26 km | 68 |
| 11Taper | Intervals10 km · 4×1 km | Easy8 km | Marathon pace10 km · 6 km | Easy6 km | Long run18 km | 52 |
| 12Race week | Easy + strides7 km · 6×20 s | Easy6 km | Marathon pace7 km · 4 km | Shakeout4 km · 4×20 s | Marathon42.2 km | 66 |
Monday and Friday are rest days. Add 20 to 30 minutes of strength after Wednesday's easy run. “+8 km” on a long run means the last 8 km at marathon pace.
Sub-4, planned around your week
Tell Paceo your race date and your days, and it builds this plan with your own paces, moves sessions when life happens, and sets your fuel for the long runs.
Why marathon pace gets so much time
Every Thursday alternates between tempo and marathon pace, and three of the long runs finish at marathon pace. By week 9 you run 12 km at 5:40 on a Thursday and finish a 32 km Sunday with 10 km at the same pace. The point is not fitness alone. It is learning, in your legs, exactly what 5:40 feels like when you are tired, so that on race day you do not need to check your watch every 200 metres.
The intervals on Tuesday raise the ceiling. A runner whose 10 km pace is 5:00 finds 5:40 comfortable for longer than one whose 10 km pace is 5:15. Do not race them: the last rep should feel like you could do one more.
Fuel like it is part of the plan
Sub-4 runners are out there long enough to run out of stored carbohydrate. Plan on 60 g of carbohydrate per hour in the race, starting at 30 minutes, and practise exactly that on every long run from week 5. Your gut adapts to carbohydrate the same way your legs adapt to distance.
For the two days before the race, eat 8 to 10 g of carbohydrate per kg of body weight a day. Paceo raises your carbohydrate targets on long-run days automatically, so the plan and the food are written together.
Race-day splits
Aim for even splits, not a time bank. Going through halfway in 1:59 to 2:00 and running the second half in the same time is how most sub-4 races are won. Runners who bank two minutes in the first half usually give back five in the last 10 km.
- 5 km
- 28:12
- 10 km
- 56:24
- Half
- 1:59:00
- 30 km
- 2:49:13
- 35 km
- 3:17:25
- Finish
- 3:58:00
Questions
- What pace do I need for a sub-4 hour marathon?
- 5:41 per km, or 9:09 per mile, gets you in at 3:59:59. Train at 5:35 to 5:40 per km so you have a few seconds of margin for crowded starts and weaving around water stations.
- Is 12 weeks enough for a sub-4 marathon?
- Yes, if you start with a 10 km of about 53 minutes and 35 to 45 km a week of running. Twelve weeks is enough to sharpen an existing base into a race. It is not enough to build the base from nothing.
- How many kilometres a week does this plan peak at?
- About 79 km in week 9. The two build blocks run from about 50 to 76 km with a deload at the end of each.
- What if I can only run four days a week?
- Drop Wednesday's easy run and keep both quality days and the long run. You lose some volume, so aim for 4:00 to 4:05 rather than 3:55. Paceo builds the plan for however many days you tell it you have.
- Should I run the long runs at marathon pace?
- Only the marked sections. The rest of each long run is easy, 30 to 60 seconds per km slower than race pace. Running whole long runs at race pace leaves you too tired for the sessions that actually build speed.
Start the clock with a three
Get a sub-4 marathon plan built for your days and your current fitness, adjusted every morning.