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26-week 100K ultra training plan (variations included)

A 26-week 100K ultra training plan with week-by-week time-on-feet structure, hills, back-to-backs, adaptation rules, and cutoff planning tools.

Last updated/Feb 03, 2026, 02:17 PM

At a glance

Plan length

26 weeks

Built with phases, cutbacks, and a taper you can actually execute.

Weekly rhythm

47 days/week

Choose one variant and follow it for 2 weeks before tweaking.

Typical session time

Easy: ~50m • Long: ~220m

Prefer consistent minutes over heroic single sessions.

Readiness gate

  • You can complete 60–90 minutes easy without breaking down.
  • You’re willing to train by time-on-feet (not ego pace).

Default recommendation

4 days/week (Beginner-friendly)

Start here to reduce decision fatigue. Customize only after your first two weeks feel stable.

  • Consistency and durability first.

Safety first

This is general training information, not medical advice.

  • Recurring overuse pain under volume.
  • Inability to recover from long sessions (fix sleep/stress first).

Coaching beta

Want this adapted to your recovery?

Get coach-style adjustments when you miss sessions, sleep poorly, or feel fatigue signals.

Week by week

Structure you can scan

Use this as your decision map: what matters this week, what the long run is doing, and where you should back off.

WeekPhaseFocusLong sessionKey workoutsNotes
1BaseBuild time-on-feet and durability; keep it easy.Long easy time-on-feet (trail/road) + hiking practiceHills (controlled) + hiking efficiency • Back-to-back long sessions (scaled)
2BaseBuild time-on-feet and durability; keep it easy.Long easy time-on-feet (trail/road) + hiking practiceHills (controlled) + hiking efficiency • Back-to-back long sessions (scaled)
3BaseBuild time-on-feet and durability; keep it easy.Long easy time-on-feet (trail/road) + hiking practiceHills (controlled) + hiking efficiency • Back-to-back long sessions (scaled)
4BaseBuild time-on-feet and durability; keep it easy.Long easy time-on-feet (trail/road) + hiking practiceHills (controlled) + hiking efficiency • Back-to-back long sessions (scaled)Cutback week
5BaseBuild time-on-feet and durability; keep it easy.Long easy time-on-feet (trail/road) + hiking practiceHills (controlled) + hiking efficiency • Back-to-back long sessions (scaled)
6BaseBuild time-on-feet and durability; keep it easy.Long easy time-on-feet (trail/road) + hiking practiceHills (controlled) + hiking efficiency • Back-to-back long sessions (scaled)
7BaseBuild time-on-feet and durability; keep it easy.Long easy time-on-feet (trail/road) + hiking practiceHills (controlled) + hiking efficiency • Back-to-back long sessions (scaled)
8BaseBuild time-on-feet and durability; keep it easy.Long easy time-on-feet (trail/road) + hiking practiceHills (controlled) + hiking efficiency • Back-to-back long sessions (scaled)Cutback week
9BuildAdd terrain specificity and back-to-back durability.Back-to-back long sessions (scaled) + fueling rehearsalHills (controlled) + hiking efficiency • Back-to-back long sessions (scaled)
10BuildAdd terrain specificity and back-to-back durability.Back-to-back long sessions (scaled) + fueling rehearsalHills (controlled) + hiking efficiency • Back-to-back long sessions (scaled)
11BuildAdd terrain specificity and back-to-back durability.Back-to-back long sessions (scaled) + fueling rehearsalHills (controlled) + hiking efficiency • Back-to-back long sessions (scaled)
12BuildAdd terrain specificity and back-to-back durability.Back-to-back long sessions (scaled) + fueling rehearsalHills (controlled) + hiking efficiency • Back-to-back long sessions (scaled)Cutback week
13BuildAdd terrain specificity and back-to-back durability.Back-to-back long sessions (scaled) + fueling rehearsalHills (controlled) + hiking efficiency • Back-to-back long sessions (scaled)
14BuildAdd terrain specificity and back-to-back durability.Back-to-back long sessions (scaled) + fueling rehearsalHills (controlled) + hiking efficiency • Back-to-back long sessions (scaled)
15BuildAdd terrain specificity and back-to-back durability.Back-to-back long sessions (scaled) + fueling rehearsalHills (controlled) + hiking efficiency • Back-to-back long sessions (scaled)
16BuildAdd terrain specificity and back-to-back durability.Back-to-back long sessions (scaled) + fueling rehearsalHills (controlled) + hiking efficiency • Back-to-back long sessions (scaled)Cutback week
17BuildAdd terrain specificity and back-to-back durability.Back-to-back long sessions (scaled) + fueling rehearsalHills (controlled) + hiking efficiency • Back-to-back long sessions (scaled)
18PeakRace-specific long sessions + cutoff-aware pacing.Key long session with terrain focus + cutoff pacing practiceHills (controlled) + hiking efficiency • Back-to-back long sessions (scaled)
19PeakRace-specific long sessions + cutoff-aware pacing.Key long session with terrain focus + cutoff pacing practiceHills (controlled) + hiking efficiency • Back-to-back long sessions (scaled)
20PeakRace-specific long sessions + cutoff-aware pacing.Key long session with terrain focus + cutoff pacing practiceHills (controlled) + hiking efficiency • Back-to-back long sessions (scaled)Cutback week
21PeakRace-specific long sessions + cutoff-aware pacing.Key long session with terrain focus + cutoff pacing practiceHills (controlled) + hiking efficiency • Back-to-back long sessions (scaled)
22PeakRace-specific long sessions + cutoff-aware pacing.Key long session with terrain focus + cutoff pacing practiceHills (controlled) + hiking efficiency • Back-to-back long sessions (scaled)
23PeakRace-specific long sessions + cutoff-aware pacing.Key long session with terrain focus + cutoff pacing practiceHills (controlled) + hiking efficiency • Back-to-back long sessions (scaled)
24TaperReduce load; keep a touch of specificity; arrive healthy.Shorter long session + mobilityHills (controlled) + hiking efficiency • Back-to-back long sessions (scaled)
25TaperReduce load; keep a touch of specificity; arrive healthy.Shorter long session + mobilityHills (controlled) + hiking efficiency • Back-to-back long sessions (scaled)
26TaperReduce load; keep a touch of specificity; arrive healthy.Shorter long session + mobilityHills (controlled) + hiking efficiency • Back-to-back long sessions (scaled)

Workout library

The sessions you repeat

You don’t need 50 workouts. You need a small library that you execute consistently, then progress safely.

Time-on-feet long session

Purpose: Build durable endurance without over-focusing on pace.

Prescription: 105–220+ minutes easy. Include hiking on climbs if terrain demands it.

Substitutions

  • Split into two sessions on high-stress weeks; keep total time similar.

Red flags

  • Sharp pain that changes form.
  • Needing multiple days to recover every week.
Back-to-back long sessions (scaled)

Purpose: Train durability and pacing under accumulated fatigue.

Prescription: Two consecutive days: long easy + medium easy. Keep both controlled and finish feeling stable.

Substitutions

  • If injury-prone: one long run + one long hike.

Red flags

  • Turning day 2 into a race.
  • Fatigue that spills into the entire next week.
Hills (controlled) + hiking practice

Purpose: Build climbing efficiency and downhill resilience safely.

Prescription: 6–12 × 2–4 min uphill at controlled effort; hike steep reps. Jog easy down.

Substitutions

  • Stair climbing or incline treadmill if needed.

Red flags

  • Knee pain on descents.
  • Over-striding downhill.
Cutoff pacing rehearsal

Purpose: Practice pacing that keeps you safe against cutoffs without burning matches.

Prescription: 60–120 min with segments at your cutoff-safe effort. Practice aid-station efficiency (quick in/out).

Substitutions

  • Do it as a hike-run combo on trails.

Red flags

  • Chasing pace on terrain that demands hiking.
  • Skipping fueling while ‘testing’ pace.
Fueling practice (GI-friendly)

Purpose: Train your gut and reduce race-day surprises.

Prescription: On long sessions: practice a simple schedule and adjust products if GI issues appear.

Substitutions

  • Lower intensity + smaller doses if tolerance is low.

Red flags

  • Repeated GI distress without changes.
  • Ignoring hydration in heat.
Strength durability (lower-body + trunk)

Purpose: Support downhill resilience and long-duration posture.

Prescription: 2×/week, 25–40 min: single-leg, posterior chain, calves, trunk. Avoid soreness spikes.

Substitutions

  • Travel circuit with step-ups, calf raises, core.

Red flags

  • DOMS ruining long sessions.
  • Sharp joint pain.

Adaptation rules

What to do when life happens

Most training failures are not fitness failures — they’re pacing, sleep, or scheduling failures. Use simple rules.

Missed workout

  • Protect the long session; drop extra intensity.
  • Don’t stack back-to-backs to ‘catch up’.

Low sleep week

  • Keep it easy; reduce long-session duration by 15–25%.
  • Replace hills with hiking if needed.

Fatigue signals

  • If legs feel dead, replace with easy hike and mobility.
  • Prioritize fueling and sleep; treat it like a cutback week.

Pain or injury

  • Pain that changes gait is a stop signal.
  • Swap to hiking/biking until pain-free; return gradually.

Travel week

  • Short sessions win: keep one long hike/run and one hills touch if possible.
  • Use time-based training and stay consistent.

Tools

Numbers to train with

Pick one tool, generate outputs, then plug them into your training week.

Calculator

Ultra cutoff planner

Compute the minimum average pace to beat a cutoff, and sanity-check your buffer with a planned pace.

Example: 420 sec per km = 7:00/km.

Required pace (km)

9:36

Planned finish

Buffer vs cutoff

Limitation: this ignores elevation, trail surface, aid-station stoppage, and mandatory gear transitions. Use it as a baseline, then add margin.

Planner

Marathon fueling schedule

A simple, repeatable plan: pick a carb target, then schedule doses you can actually execute while running.

Total time

3:45:00

Total carbs

281 g

Approx gels

12 gels

Simple schedule

Take a dose every 20 minutes. In training, practice the same timing so race day is automatic.

20m40m60m80m100m120m140m160m180m200m220m

Safety note: fueling targets vary by athlete and conditions. Practice in training and adjust if you get GI distress. This is not medical advice.

Evidence (high level)

Why this structure works

  • Ultras reward time-on-feet and durability, not heroic pace sessions.
  • Back-to-back sessions train fatigue resistance safely when scaled.
  • Cutoff planning is a pacing skill; train it like a discipline.
  • Fueling and hydration are part of the training plan, not a race-week afterthought.

FAQs

Should I train by pace or time?

For ultras, time-on-feet is usually more useful than pace. Terrain changes pace; effort and durability are what transfer.

Do I need back-to-back long runs?

They can help, but they must be scaled and recovery-aware. If you’re injury-prone, use one long run and one long hike.

How do I prepare for cutoffs?

Use cutoff-safe effort in training, practice aid-station efficiency, and build margin for terrain and fatigue.

How much elevation training do I need?

Match the race demands. If the race is hilly, you need hills. If it’s flat, you still need durability.

How do I avoid GI issues?

Practice fueling early and often in long sessions. Adjust products and timing; don’t wait for race week.

What’s the biggest mistake?

Turning long sessions into races. Ultras reward staying consistent week after week.

Keep going

Sources