How Long Should Your Half Marathon Long Run Be?
The half marathon occupies a unique sweet spot in distance running. Long enough to require dedicated training, but short enough that most runners don't need to cover the full race distance in training.
Your optimal long run distance depends on several factors:
- Weekly mileage: Higher-mileage runners can handle longer long runs
- Goals: Racing vs. finishing requires different approaches
- Time available: Long runs over 2 hours require fueling practice
Typical Half Marathon Long Run Recommendations
| Weekly Mileage | Regular Long Run | Peak Long Run |
|---|---|---|
| 15-20 miles | 6-7 miles | 10 miles |
| 25-30 miles | 8-9 miles | 11-12 miles |
| 35-40 miles | 10-12 miles | 13-14 miles |
| 45+ miles | 12-14 miles | 15-16 miles |
First Half Marathon? Here's What to Know
If this is your first 13.1, your primary goal is reaching the start line healthy and the finish line happy. That means:
- Build gradually: Increase long run distance by no more than 1 mile per week
- Include cutback weeks: Every 3-4 weeks, reduce your long run by 20-30%
- Time on feet matters: For slower runners, cap long runs at 2 hours regardless of distance
- Practice race day: Use long runs to test shoes, fueling, and clothing
The 10-Mile Rule
Many coaches suggest running at least 10 miles before your first half marathon. This gives you confidence that you can cover most of the distance, while leaving something for race day magic.
Half Marathon vs. Marathon Long Runs
Compared to marathon training, half marathon long runs are:
- Shorter: Peak runs of 12-14 miles vs. 20-22 miles
- More forgiving: Missing one long run isn't race-ending
- Less demanding: Recovery is quicker, allowing more consistent training
- Quality-focused: More room for tempo work within the long run
Frequently Asked Questions
How long should my longest run be for a half marathon?
Most runners benefit from a longest run of 11-13 miles for half marathon training. First-timers should aim for at least 10-11 miles.
How many long runs should I do before a half marathon?
A typical 12-week half marathon plan includes 10-12 long runs. The key is consistency-building gradually with 3-4 runs at or near your target distance before race day.
Should I run the full 13.1 miles before my half marathon?
It's not necessary. Running 10-12 miles in training gives you the fitness needed. Race day adrenaline, proper taper, and crowd energy will carry you the final miles.
What percentage of weekly mileage should my half marathon long run be?
Long runs should typically be 25-30% of your weekly mileage. For a runner doing 30 miles per week, that's 7.5-9 miles for regular long runs, building to 10-12 miles in peak weeks.
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