Start here after a 50K, not instead of one
A 50-mile race is about 80.5 km, close to two marathons. This 18-week plan assumes you have finished a 50K or a trail marathon, you are running at least four days a week, and a long run of about 2 hours 30 is already comfortable. If that is not true, use the 50K plan first.
Awaiting publisher review. This is a general schedule from Running for Good Ultra, not a personal programme and not an independent coaching or medical review. Speak to a GP before you build on this if you have a medical condition or you have not been exercising. The NHS asks for that conversation. Easy running in this plan should stay talkable: sentences, not single words.
A 16-week version is weeks 3 to 18. Use it only if a 3-hour long run is already comfortable. Do not delete the easier weeks to make the dates fit.
Some of the long work is split over two days
Most weekends are one long run. On three weekends the long work is Saturday plus an easy Sunday. That is so you practise moving on tired legs without turning a Tuesday into a second race. On those weeks, run only twice during the week, both easy, about 45 and 60 minutes.
On the other weeks, run three times besides the long run: about 50, 60 and 65 minutes, easy. In the weeks marked hills, one of those runs includes 6 short ups of about 30 seconds, walked down, after an easy warmup. Skip hills on easier weeks and on back-to-back weeks.
From week 9, walk the steeper climbs in the long run on purpose. Eat and drink something you would actually carry, starting before you are hungry. The point is to find what you can repeat, not to clear a kilometre target.
The 18 weeks
Put the race on week 18. Follow the time. A 4-hour run on a hilly trail covers less ground than 4 hours on a flat path, and that is the right outcome.
| Week | Weekend | During the week |
|---|---|---|
| 1 | 2 hours 45 | Three easy runs, about 45, 50 and 55 minutes |
| 2 | 3 hours | Three easy runs, about 45, 55 and 60 minutes |
| 3 | 3 hours 15 | Three runs. One of them includes hills. |
| 4 | 2 hours 15 | Three shorter easy runs, about 40, 45 and 45 minutes |
| 5 | 3 hours 30 | Three easy runs, about 50, 60 and 60 minutes |
| 6 | 3 hours 45 | Three easy runs, about 50, 60 and 65 minutes |
| 7 | Saturday 3 hours 30, Sunday 90 minutes easy | Two easy runs, about 45 and 55 minutes |
| 8 | 2 hours 30 | Three shorter easy runs. Easier week. |
| 9 | 4 hours, with some planned walking | Three easy runs, about 50, 60 and 70 minutes |
| 10 | 4 hours 15 | Three runs. One of them includes hills. |
| 11 | Saturday 4 hours, Sunday 2 hours easy | Two easy runs, about 50 and 60 minutes |
| 12 | 2 hours 45 | Three shorter easy runs. Easier week. |
| 13 | 4 hours 45 | Three easy runs, about 55, 65 and 70 minutes |
| 14 | Saturday 4 hours 30, Sunday 2 hours easy | Two easy runs, about 50 and 60 minutes |
| 15 | 5 hours. Peak. Walk, eat, and finish composed. | Three easy runs, about 50, 60 and 60 minutes |
| 16 | 3 hours 30 | Three easy runs, about 45, 50 and 55 minutes |
| 17 | 2 hours | Three easy runs, about 30, 40 and 40 minutes |
| 18 | Race | Two or three easy runs of 20 to 30 minutes early in the week |
Keep the easier weeks when life interrupts
If you miss the long run, repeat that week once. Do not add the missed hour to the next weekend. If illness or injury takes two weekends, pick a later race. The last fortnight is for arriving fresh, not for replacing a month of long runs.
Stop and get medical care for chest pain, dizziness, fainting, or pain that changes how you move. A 50-mile cutoff can be 13 hours or much more, depending on the race. This plan does not calculate that for you.
Sources & further reading
Awaiting publisher review. This is a general schedule from Running for Good Ultra, not a personal programme and not an independent coaching or medical review. Back-to-back weekends are a planning choice in this schedule, not a claim that one arrangement suits every runner.
Found something that needs correcting? Let us know.