Marathon Training Guide
How to Run a Sub-3:45 Marathon
A sub-3:45 marathon requires averaging 5:20 per kilometer - a meaningful step up from sub-4 that demands more structured training and better pacing discipline.
Pace /km
5:20
Pace /mile
8:35
Speed
11.3 km/h
What are the prerequisites to run a 3:45:00 Marathon?
Half Marathon Time
Under 1:45 indicates sub-3:45 marathon potential
Long Run Capability
32 km with final 10 km at goal pace
Weekly Mileage
50-70 km per week for at least 10-12 weeks
Key Training Principles
Follow these principles to build the fitness needed for your goal.
Build Mileage
Target 50-70 km per week with gradual progression.
Example: Build to 60-65 km per week at peak training
Long Run Development
Build to 32-35 km with race-pace segments.
Example: 32 km with kilometers 18-28 at 5:20/km
Tempo Work
Extended threshold runs to build stamina.
Example: 40-50 minutes at 5:05-5:10/km pace
Speed Maintenance
Keep some faster running to maintain efficiency.
Example: 6×1km at 4:50/km with 2 min recovery
Recovery Focus
Easy days must be easy to handle the volume.
Example: Recovery runs at 6:00-6:30/km pace
Sample Training Week
Here is what a typical training week might look like.
| Day | Workout | Details |
|---|---|---|
| Monday | Rest | Complete rest or light mobility |
| Tuesday | Intervals | 6×1km at 4:50/km with 2min recovery |
| Wednesday | Easy Run | 10 km at conversational pace |
| Thursday | Tempo Run | 45 min at 5:10/km pace |
| Friday | Easy Run | 6 km recovery |
| Saturday | Long Run | 28-32 km with MP segments |
| Sunday | Easy Run | 8 km recovery run |
Want a personalized training plan tailored to your schedule and fitness level?
Race Day Strategy
Follow this race day execution plan to hit your goal.
- 1
Light warm-up: 5-10 minutes easy, dynamic stretches
- 2
Start at goal pace (5:20/km) - first 10K should feel very controlled
- 3
Hit halfway at 1:52:30 feeling good
- 4
Fuel consistently every 30-40 minutes
- 5
Kilometers 30-35: stay focused, maintain form
- 6
Final 10K: execute your finish, empty the tank
Common Mistakes to Avoid
- Going out at sub-5:00/km pace
- Insufficient marathon-pace practice
- Not respecting the distance
- Fueling too little or too late
- Inadequate taper
Frequently Asked Questions
Yes, a sub-3:45 marathon is a strong performance that puts you ahead of most recreational marathoners.
Related Goals
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