Breaking two hours in the half marathon is a milestone for a reason: it's ambitious for a new runner, but within reach for many people who train consistently for a few months. Here's what it actually requires.
The numbers
A half marathon is 21.0975 km. To finish in under 2:00:00, you need an average pace of 5:41 per kilometre – and in practice a little faster, because GPS distances in races usually come out longer than the official course and the start costs you a few seconds.
Your checkpoints at exactly 2-hour pace:
| Distance | Time |
|---|---|
| 5 km | 28:26 |
| 10 km | 56:53 |
| 15 km | 1:25:19 |
| 20 km | 1:53:45 |
| 21.1 km | 2:00:00 |
Many runners aim for about 5:35–5:38 per km to leave a small buffer.
How fit do you need to be?
A useful rough check is a recent race over a shorter distance. Peter Riegel's well-known formula estimates how pace slows as distance grows. By that formula, a 2-hour half marathon corresponds to roughly:
- 10 km in about 54–55 minutes
- 5 km in about 26 minutes
Treat these as a guide, not a promise. The formula assumes you've trained for the longer distance. With little long-run training, your half marathon will usually be slower than predicted.
If your current 10 km time is well above an hour, sub-2 is still a realistic goal – just a goal for a longer build, perhaps the next season rather than the next race.
The building blocks
Different plans use different details, but most good half-marathon training rests on the same four pieces:
- Easy running, most of the week. Conversational pace. This is the base everything else stands on.
- One long run a week, built up gradually to roughly 16–19 km or 1:45–2:00 hours at easy effort.
- One quality session a week – tempo runs or intervals, depending on the phase. Tempo work around 5:15–5:30/km is especially relevant for a 5:41 race pace.
- Recovery and a taper. Easier weeks every few weeks, and lighter training in the final 1–2 weeks.
A typical week in the middle of a build might look like this for someone running four times a week:
- Tuesday: easy 40 minutes + 4–6 strides
- Thursday: tempo session, e.g. 3 × 8 minutes at tempo effort with 2 minutes easy
- Saturday: easy 30–40 minutes
- Sunday: long run, easy
Most people need 10–16 weeks of this kind of training if they can already run 30–40 minutes comfortably. Coming from zero, give yourself longer.
If you'd rather not plan the weeks yourself, a training app that adapts the plan to your schedule can take care of the structure. Whatever you use, the principles above are what a good plan should contain.
Race-pace practice
In the last 4–6 weeks, include some running at goal pace so 5:40/km feels familiar – for example 2 × 15 minutes at race pace in the middle of a run, or the final 15–20 minutes of a long run. The aim is rhythm, not exhaustion.
Signs you're ready
- You've run a 10 km in around 54–55 minutes, or a tempo session of 20+ minutes near 5:20/km felt controlled.
- Your long run has reached 16 km or more at easy effort without lasting soreness.
- You've practised eating and drinking on long runs.
On race day
Start controlled. The most common reason people miss sub-2 by a minute or two is the first 5 km: too fast in the crowd, paid back with interest after 15 km. A pacing group is a good idea if the race has one – runners who run with pacers are far more likely to keep an even pace.
The bottom line
Sub-2 isn't about secret workouts. It's about a few months of mostly easy running, a long run that grows patiently, one good session a week, and a disciplined first half on race day.
Sources
- Riegel PS. Athletic records and human endurance. American Scientist. 1981;69(3):285–290.
- Smyth B. Fast starters and slow finishers: a large-scale data analysis of pacing at the beginning and end of the marathon for recreational runners. J Sports Analytics. 2018. doi:10.3233/JSA-170205
- Seiler S. What is best practice for training intensity and duration distribution in endurance athletes? Int J Sports Physiol Perform. 2010;5:276–291. doi:10.1123/ijspp.5.3.276