Long runs are not races
The long run sits at 62–72% of VO2max — slower than marathon pace and often slower than easy pace on tired legs. Its job is time on feet, glycogen depletion and the adaptation that follows, not speed. A marathon long run at goal pace every week is a common way to arrive at the start line fatigued.
How long is long?
For a marathon, 28–32 km or 2:30–3:00 is the standard peak. For a half, 16–19 km is enough; for 5K and 10K, 10–14 km. The long run should be 25–30% of weekly volume, which is a useful check: if a 30 km run is half your week, the week is too small for the race you are training for.
Fuel and finish
Anything beyond 75 minutes is worth fuelling, starting at 30–60 g of carbohydrate per hour. Practise it on long runs, not on race day. Finish feeling like you could run another 5 km — that is the correct effort, and it is why the pace range here is deliberately modest.
Frequently Asked Questions
Should long runs be faster?
Only the last 10–20 minutes at marathon pace, and only for marathon training. The bulk should stay easy.
Can I split a long run?
Two runs in a day is not equivalent — the adaptations depend on continuous time. It is better than nothing if scheduling forces it.
How many long runs before a marathon?
Eight to twelve, building gradually, with two or three at peak distance and a three-week taper.
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