How To Structure Your Long Runs For Ultra Marathon Training
When it comes to scheduling your long runs for ultra marathon training you'll get a lot of different opinions. Some say anything over 20 miles isn't necessary. Others will say that total weekly volume is better. Then you have the crowd who insists back to back long runs are the only way to go. Last but not least you get the real crazies who say 6-8 hour long runs are necessary.
So who's right? Well, none are technically wrong but I believe there is an ideal way to schedule your long runs for ultra marathon training based on 4 week training blocks. That's what we will discuss in this blog post
The truth is, ultra training isn’t about picking a side in that debate it’s about applying the right stimulus at the right time. That’s where structuring your long runs inside 4-week training blocks becomes incredibly effective. It gives you progression, recovery, and specificity without burning you out or leaving you underprepared.
Why 4 Week Blocks Work
Think of your training like a wave instead of a straight line. You build, build, build… then absorb.
A 4-week block typically looks like this:
- Week 1: Establish
- Week 2: Build
- Week 3: Peak
- Week 4: Recover (deload)
This structure lets your body adapt to increasing stress while minimizing the risk of injury or overtraining. More importantly, it allows you to vary your long run strategy instead of forcing the same approach every weekend.
How to Structure Your Long Runs
Instead of asking “How long should my long run be?” the better question is: What is the purpose of this week’s long run?
Each week in the block should have a different goal.
Week 1: The Foundation Long Run
This is your “steady and controlled” effort.
You’re not trying to prove anything here. You’re just setting the tone for the block.
Week 2: The Progression Long Run
Now you start adding a bit of stress.
- Slightly longer than Week 1
- Option to finish the last 20–30% stronger
- Continue practicing race-day habits
This run should feel like a stretch but still manageable.
Week 3: The Peak Stimulus
This is your most important long run of the block.
And no, that doesn’t automatically mean your longest single run ever.
You have two strong options here:
- Single Long Run: Push duration (but cap it wisely...usually 3.5 to 5 hours for most runners)
- Back-to-Back Long Runs: Split the load across two days (e.g., 3 hours Saturday + 2 hours Sunday)
Back-to-backs are especially useful for ultras because they simulate fatigue without requiring one massive, high-risk effort.
Week 4: The Deload Long Run
This is where most runners mess up.
Your long run should decrease significantly here:
- Reduce volume by 30–50%
- Keep effort easy
- Let your body absorb the previous three weeks
You don’t gain fitness during the hardest weeks you gain it during recovery.
What About 6–8 Hour Runs?
Let’s address the elephant in the room.
Do you need 6–8 hour training runs?
For most runners: no.
Longer doesn’t always mean better, it often just means more fatigue, longer recovery, and higher injury risk. You can get the same (or better) adaptations by stacking fatigue intelligently through back-to-backs and consistent weekly volume.
The exception? Highly experienced runners targeting very long events (100 miles or more) who understand how their body responds. Even then, it’s used sparingly not every weekend.
Weekly Volume Still Matters
Long runs don’t exist in a vacuum.
If your long run is huge but the rest of your week is minimal, you’re not building durable fitness, you’re just surviving one big effort at a time.
A better approach:
- Keep your long run around 20–35% of your weekly volume
- Support it with consistent midweek mileage
- Include easy runs that actually stay easy
Consistency beats hero workouts every time.
Putting It All Together
Here’s a simple example of a 4-week progression:
- Week 1: 2.5-hour long run
- Week 2: 3-hour long run
- Week 3: 3 hr + 2 hr back-to-back
- Week 4: 1.5–2-hour deload run
Then you repeat the cycle, slightly increasing the overall load or adjusting based on how your body responds.
Final Thoughts
There isn’t one “perfect” long run strategy for ultra marathon training but there is a smart way to organize them.
When you use 4-week blocks, you stop guessing and start progressing with purpose. You get the benefits of different training philosophies without committing to extremes that can derail your training.
And maybe most importantly, you stay healthy enough to actually make it to the start line.
At the end of the day, the best long run plan is the one you can consistently execute.
