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Running · 24 weeks24-week 50 km ultra training plan
A 24-week 50 km ultra training plan takes a runner on 55 km a week with a 4:00 marathon behind them from where they are to race day in 24 weeks, building to 91 km in the biggest week. It spends 9 weeks in base, 10 weeks in build, 2 weeks in peak, 2 weeks in taper, with 5 lighter weeks to absorb the work, on 6 days a week.
Build my 50 km ultra plan — freeBuilt from your own numbers and your own week. The first week is free.
24 weeks is a comfortable length for a 50 km ultra. There is room for a proper base before the harder work, lighter weeks to absorb it, and a taper that leaves you fresh rather than flat.
What the weeks are for
| Base | 9 weeks — aerobic volume, mostly easy, the foundation everything else stands on |
|---|---|
| Build | 10 weeks — the harder sessions arrive and volume keeps climbing |
| Peak | 2 weeks — the biggest, most race-specific weeks |
| Taper | 2 weeks — volume drops, intensity stays, you arrive fresh |
| Lighter weeks | 5, roughly every fourth week |
| Total | 1648 km, 213 hours |
The 24 weeks
Generated for a runner on 55 km a week with a 4:00 marathon behind them.
| Week | Phase | Volume | Load | |
|---|---|---|---|---|
| 1 | Base | 55 km | 312 | |
| 2 | Base | 58 km | 330 | |
| 3 | Base | 61 km | 344 | |
| 4 | Base · down | 42 km | 243 | |
| 5 | Base | 64 km | 358 | |
| 6 | Base | 67 km | 377 | |
| 7 | Base | 70 km | 391 | |
| 8 | Base · down | 48 km | 276 | |
| 9 | Base | 73 km | 409 | |
| 10 | Build | 72 km | 430 | |
| 11 | Build | 75 km | 445 | |
| 12 | Build · down | 54 km | 315 | |
| 13 | Build | 78 km | 461 | |
| 14 | Build | 81 km | 476 | |
| 15 | Build | 84 km | 491 | |
| 16 | Build · down | 60 km | 353 | |
| 17 | Build | 87 km | 506 | |
| 18 | Build | 89 km | 523 | |
| 19 | Build | 91 km | 529 | |
| 20 | Peak · down | 61 km | 371 | |
| 21 | Peak | 90 km | 521 | |
| 22 | Taper | 77 km | 435 | |
| 23 | Taper | 60 km | 347 | |
| 24 | Race · race | 55 km | 482 |
The biggest week, session by session
Week 19, build phase — the heaviest week of the block.
| Monday | Easy run — 1h12, 10.4 km |
|---|---|
| Monday | Strength — lower body — 0h41 |
| Tuesday | Threshold — 3 × 10 min — 1h06, 10.2 km |
| Tuesday | Strength — lower body — 0h41 |
| Wednesday | Easy run — 1h12, 10.4 km |
| Friday | Race pace — 9 km — 1h13, 11.4 km |
| Saturday | Easy run — 1h16, 11 km |
| Sunday | Long run with a fast finish — 3h59, 37.2 km |
The paces
| Pace band | Per kilometre |
|---|---|
| Easy — the ceiling, not the target | 6:23 |
| Marathon pace | 5:44 |
| Threshold | 5:25 |
| Interval (VO₂max) | 4:54 |
Computed from VDOT 37.9, derived from that time trial using Jack Daniels' model. Your own numbers will differ — the plan builds these from a time trial you enter.
What this plan says out loud
Your race is 25 weeks away. This plan covers the last 24 weeks, which is as far ahead as a specific plan is worth writing. Keep training as you are until then.
Some sessions have been cut to fit the time you said you have — 75 minutes on a weekday and 240 at the weekend. That is a real constraint and the plan respects it, but be aware the long session is the one that matters most: if you can find more time anywhere, find it on the weekend.
On 6 days a week there is nowhere to put 40 km without prescribing runs nobody should be doing. The plan caps individual easy runs at 14 km and carries less volume than your target as a result. More days would do more for you than longer runs.
Common questions
Is 24 weeks enough for a 50 km ultra?
Yes, for most people who already exercise. We would choose at least 20 weeks, and this is 24.
How many days a week does it train?
6, on Monday, Tuesday, Wednesday, Friday, Saturday, Sunday in this example. You tell the plan which days you actually have, and it never puts two hard days back to back.
What is the longest session?
Long run with a fast finish, about 4h00 and 37 km. It is capped by share of the week, by absolute length, and by the time you say you have.
Can I use this if I train at altitude?
Yes, and you should say so when you build it. Paces and power are corrected for the difference between where you tested and where you train — in Johannesburg that is roughly 8%, or about 26 seconds a kilometre on an easy run for a 20-minute 5 km runner.