A half marathon is the most forgiving distance to train for badly — a good week of volume and a hilly Sunday will drag most people through it. That's also why it rewards a smart plan so much. The half sits exactly between the 10K and the marathon: it keeps the 10K's two quality sessions, but adds enough endurance that the long run starts to matter, and it's long enough that your race pace becomes the whole point of training.
The key insight: for most runners, half-marathon pace is very close to threshold. That single fact shapes the entire plan. Much of your quality is sustained work around race pace — controlled, specific, and trainable — while VO2max work stays on the menu as a secondary session rather than the engine.
Priority hierarchy (what to protect when life gets in the way):
Five to six days a week, two quality sessions plus a long run, and everything else genuinely easy. Unlike a marathon plan there is a dedicated faster session every week — but it's not a death march, and it rotates with hills and classic VO2max reps.
| Day | Session | Purpose |
|---|---|---|
| Mon | Rest / recovery | Absorb the long run + weekend |
| Tue | Quality #1 — threshold / HM-specific | The key workout: race-pace economy |
| Wed | Easy | Aerobic volume |
| Thu | Quality #2 — VO2max / hills | Aerobic power + running economy |
| Fri | Recovery / rest | Absorb the week's work |
| Sat | Easy + strides | Volume + neuromuscular speed |
| Sun | Long run (16–22 km) | Endurance + race-pace practice |
The Tuesday session is the personality of the plan: sustained, controlled speed around race pace or just under it. Because HM pace and threshold overlap so much, the same workout serves both — building the engine and rehearsing the race. Rotate the classics:
Keep them controlled (RPE 7–8/10). Stamina is the point, not grinding. Practised consistently, HM pace stops being scary and starts being your pace.
No 30–35 km slogs here. The half long run develops from an easy 14–16 km up to about 20–22 km — long enough to build serious endurance, short enough that you recover properly and can still hit two quality sessions the same week. Most of it stays easy and conversational:
The pattern matters: build the distance first, then bolt on race-pace practice. Ending a long run at HM effort teaches you to hold a strong, specific pace when you're a little tired — exactly the situation the second half of the race presents. It's less destructive than a marathon long run, which is precisely why you can do it every week without collapsing.
Unlike a marathon plan, the half keeps a faster session every Thursday — but it's a complement, not a weekly crucible. VO2max work raises the ceiling your threshold sits against, and hills build power without the pounding. Rotate them:
These are 5K-effort reps: hard but controlled, good form on every one. The daily mission is aerobic power and economy — never a race against the clock that leaves the rest of the week shot.
Two quality sessions and a long run work only if the other days let you recover. Easy days are actually easy — conversational, comfortable, no heroics. Saturday's easy run finishes with 4–6 × 20 sec strides (fast/relaxed, full easy recovery) to keep your legs fast without fatigue. After Tuesday's quality and before Thursday's, everything in between should feel like a coast.
The half plan has exactly two hardish days plus a long run. The moment you add a third quality session — say, threshold Tuesday, intervals Thursday, and a tempo Wednesday — you're running a shorter-distance plan with extra miles attached, and the quality collapses. If you need more, add volume to the easy days, not another hard session.
A typical 8–12 week half build (longer for lower fitness) splits into four phases plus a modest taper.
Build volume, keep the long run easy and progressive (14 → 17 km), establish both quality sessions.
Long runs reach 18–19 km, and the Tuesday session starts edging toward race pace.
The race becomes the template. Long runs carry final HM-effort blocks; Tuesday is HM-pace work pure and simple.
The biggest long run of the block — 20–22 km with 3 × 3 km @ HM pace embedded. Let the week stand as the proof you're ready.
Most half plans need only ~10 days, and they keep more intensity than a marathon taper because the demand is lower.
The framework flexes to four to seven runs a week.
Volume first, intensity second. Keep the two quality sessions and the long run; let the easy days take the hit when a week goes sideways. And because half-marathon pace and threshold are close, getting the threshold right — controlled, sustainable, practised — is most of the battle.
Our half-marathon plan generator builds exactly this architecture — Tuesday threshold/HM-specific work, Thursday VO2max or hills, a Sunday long run that develops to 20–22 km with race-pace blocks, and a modest ~10-day taper — personalized to your fitness and synced to your Garmin watch.
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