Training guide
Half Marathon Training Guide
A half marathon plan is built on a progressively longer weekly long run, supported by easy aerobic mileage and one threshold session. Plans typically run 10–12 weeks across 4–5 days. The long run is the keystone — it teaches your body to sustain effort for 21.1 km — while tempo runs sharpen the pace you can hold on race day.
- Plan length
- 10–12 weeks
- Weekly volume
- 4–5 sessions, ~40–70 km
Overview
The half marathon is long enough that endurance dominates, but fast enough that threshold pace still matters. Training pairs a growing long run with one weekly tempo session and plenty of easy aerobic mileage.
The long run is where the race is won or lost. It climbs gradually — never more than about a 10% jump week to week — and later in the plan often finishes with a few kilometres at goal half-marathon pace to rehearse race effort on tired legs.
A typical training week
| Mon | Rest or easy run |
|---|---|
| Tue | Intervals or hills (e.g. 6 × 800m at 10K effort) |
| Wed | Easy run |
| Thu | Tempo run (25–35 min at threshold) |
| Fri | Rest or easy run |
| Sat | Easy run + strides |
| Sun | Long run (90 min–2 hr, building) |
Key workout types
Long run
The keystone session — builds the endurance to sustain 21.1 km.
Tempo run
Threshold-pace running to raise sustainable speed.
Goal-pace segments
Kilometres at race pace late in long runs to rehearse effort.
Easy runs
Aerobic base and recovery.
Pacing reference
Finish times across a range of even paces. Find your target, then use the pace calculator for exact splits.
| Pace /km | Pace /mi | Finish |
|---|---|---|
| 5:00 | 8:03 | 1:45:29 |
| 5:30 | 8:51 | 1:56:02 |
| 6:00 | 9:39 | 2:06:35 |
| 6:30 | 10:28 | 2:17:08 |
| 7:00 | 11:16 | 2:27:41 |
Frequently asked questions
How long should my longest run be before a half marathon?
Most plans peak at 18–20 km, two to three weeks before race day, then taper. You do not need to run the full distance in training.
How many weeks to train for a half marathon?
Ten to twelve weeks if you can already run comfortably for 45 minutes. Allow longer if you are building from scratch.
What pace should I run my long runs?
Easy — roughly 60–90 seconds per kilometre slower than goal race pace, with optional race-pace finishes later in the plan.
Should I taper before a half marathon?
Yes. Reduce volume by 30–50% over the final one to two weeks while keeping a little intensity so you arrive fresh and sharp.
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