Built on time on feet
In 100 km runners, weekly volume and training speed were the strongest training predictors of race time (Knechtle 2010), and ultra runners lean on volume far more than marathoners do (Rüst 2012). So the backbone is weekly hours: about 9 at the peak for a first 100k or 50 miler, 11 for experienced and 13 for competitive runners.
Most of it is easy. Quality is one hill session a week, plus a tempo or steady run on six-day plans.
The long weekend
The long run takes about half the week in build and peak, and a back-to-back the day after takes another fifth. Long runs alternate power-hiking days, steady finishes and race rehearsals in race kit with race food. The last peak week holds the longest run.
Climbing, hiking and fuelling
Enter the race's total climb and weekly climbing builds toward it. Hike anything steep: walking costs less than running above about 16 degrees. Every run of two hours or more carries the ISSN fuelling target of 30 to 50 g carbohydrate and 450 to 750 mL fluid per hour.
Sample plans by level
How it works
- 1Pick your race date or week count. Enter the race date and the plan counts back to next Monday, or choose the number of weeks. The 100k and 50 mile default is 20 weeks.
- 2Choose your running days. Four to six days. The long run, then the back-to-back the day after, then a rest day.
- 3Pick your experience and the race's climbing. First ultra, experienced or competitive sets the weekly hours. The race's total climb sets the weekly climbing targets.
- 4Get the plan and the PDF. Every week, every session in minutes and effort, with climbing and fuelling notes. Download the PDF or copy the link.
Frequently asked questions
Why is the plan in hours and effort instead of pace?
On trail the same effort is 5 minutes per km on a flat path and 15 on a steep climb. Pace would be wrong most of the time, so every session is minutes at an effort: easy, steady, threshold or hard, with RPE and heart rate.
How much should I eat during a trail ultra?
The International Society of Sports Nutrition recommends 150 to 400 kcal per hour, with 30 to 50 g carbohydrate, plus 450 to 750 mL fluid and extra sodium. Every long run of two hours or more carries that note, so you practise it in training.
When should I hike instead of run?
On steep climbs. Walking costs less energy than running on inclines steeper than about 16 degrees (Giovanelli 2016), and the most economical mountain paths are around 20 to 30 percent. The plan puts power hiking into long runs and has a power-hike repeat session.
What is a back-to-back long run?
A second long-ish run the day after the long run, easy, on tired legs. It rehearses the second half of an ultra without one very long run. It is common coaching practice rather than something trials have tested, so the plan keeps it at about a fifth of the week.
Is the plan really free?
Yes, forever, with no account and no email. The plan and the PDF are yours. If you want a coach who adapts it to how each week went, that is what Coach Kalle does.
Is the plan the same for 100k and 50 miles?
Yes. 50 miles is 80 km, close enough to 100 km that the training is the same: long days on your feet, back-to-backs, climbing and fuelling. Set the climbing to your race and the plan adapts the weekly targets.
Sources
- Tiller NB, et al. International Society of Sports Nutrition position stand: nutritional considerations for single-stage ultra-marathon training and racing. J Int Soc Sports Nutr 2019;16:50.
- Giovanelli N, et al. Energetics of vertical kilometer foot races; is steeper cheaper? J Appl Physiol 2016;120(3):370-375.
- Minetti AE, et al. Energy cost of walking and running at extreme uphill and downhill slopes. J Appl Physiol 2002;93(3):1039-1046.
- Knechtle B, et al. Predictor variables for a 100-km race time in male ultra-marathoners. Percept Mot Skills 2010;111(3):681-693.
- Rüst CA, et al. Similarities and differences in anthropometry and training between recreational male 100-km ultra-marathoners and marathoners. J Sports Sci 2012;30(12):1249-1257.
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Last updated 6 September 2026.