Distance
100 km
100K
training plan
A 100K running plan that builds high-end ultramarathon durability with bigger weekly volume, long-run resilience, and disciplined fueling practice.
Plan length
20 weeks
Weekly distance
80-120 km
Long run range
40-50 km
How this 100K running plan works
This 100K running plan uses a 20-week build to prepare you for 100 km with weekly mileage that generally lands in the 80-120 km range. Long runs build toward 40-50 km, so the training load stays aligned with the demands of the distance.
Combine high weekly volume, longer long runs, and recovery discipline with fueling practice that supports many hours on the move. Expect higher time-on-feet demands, more deliberate fueling, and recovery habits that matter just as much as the biggest workouts.
Who this plan is for
Use these quick cues to decide whether this training block fits your current running level and where it sits in your longer progression.
Best for
Experienced ultrarunners who already tolerate high mileage and need a bigger build for very long race days.
Training focus
Combine high weekly volume, longer long runs, and recovery discipline with fueling practice that supports many hours on the move.
Progression fit
Move into 100K preparation only after building a strong base through marathon or 50K training and proving you can absorb bigger endurance blocks.
Key sessions in this plan
These sessions shape the week and show how the plan balances easy running, quality work, and endurance development for race day.
- Long runs that extend time on feet and fueling practice
- Back-to-back weekend endurance sessions
- Recovery weeks to absorb high-volume training
Across the block, weekly running typically lands around 80-120 km with long runs in the 40-50 km range.
Compare training plans
If you want a gentler build, a faster plan at the same distance, or the next step up in mileage, start with these related options.
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