Training plans
Half marathon training plan
21.1 km, first time or faster. pacr's coach writes the weeks from your answers, and rules keep the long run and the weekly growth sensible.
How it works
A few questions, then your plan
The plan builder in the app asks what a coach would, in this order.
Your goal
Finish a half marathon, or race it for a time.
Your date
Race day, or how many weeks you have.
Your running now
Your experience, how much you run today and any recent results.
Your days
Which days you can run, your long-run day and how long a run can be.
Written by AI, checked by rules
A plan you can actually follow
pacr's coach writes your weeks from your answers. Before you see them, the app checks every week against its training rules and fixes anything that breaks one.
- Starts where you areWeek one is close to what you run now.
- Grows gentlyNo week jumps far past your biggest week so far, and three weeks that climbed earn a lighter one.
- One long run a weekNever past the cap for your level, and never a sudden leap.
- Hard days apartQuality sessions are capped each week, never back to back, and none in race week.
- Careful after a breakComing back from an injury or illness? The plan starts light, with no hard sessions.
- Inside your limitsRuns only on your run days, within the minutes you have, at paces between what you run today and your goal.
The numbers behind a half marathon plan
From the app's training rules.
| You are | Weeks it needs | Longest run |
|---|---|---|
| New to running | 16 weeks | 18 km |
| Running regularly | 10 weeks | 20 km |
| Experienced | 8 weeks | 23 km |
With fewer weeks, the builder tells you the plan is a stretch before it builds. The longest run is the most the plan will ever schedule, and less if you set a time limit. The taper is up to 2 weeks, less on a short plan.
The block
How a half marathon plan is built
Every plan moves through four phases. How long each one lasts depends on the weeks you have.
Base
Time on your feet at an easy pace. Slow is correct.
Build
Weekly distance and the long run grow, with a lighter week after every three that climbed.
Peak
The biggest weeks and the longest run. Practise race-day shoes, breakfast and pacing.
Taper
Up to two lighter weeks before race day, which is the last day of the plan.
Run it
From week one to the start line
- On your wristPlan workouts can go to Apple Watch.
- A voice coachSpeaks your splits and pace while you run.
- Personal bests and badgespacr keeps your best 5K, 10K, half and marathon, and badges as you go.
- Your other appsImport from Apple Health and Health Connect, and connect Garmin and WHOOP.
- Shoe mileageSee how far each pair has gone.
Half marathon training questions
How long does it take to train for a half marathon?
The builder calls a date fewer than 16 weeks away a stretch for someone new to running, 10 for a regular runner and 8 for an experienced one. Plans run from 3 to 24 weeks.
How long is the longest run?
Never more than 18 km for someone new to running, 20 km for a regular runner and 23 km for an experienced one, and shorter if you set a time limit on your long run.
Who writes the plan?
pacr's coach, an AI, writes the weeks from your answers. Then pacr checks every week against its training rules and fixes anything that breaks one, before you see it. If the coach can't finish, or its plan fails the checks, you can use pacr's standard plan, built from the same answers and limits.
Can I do it on my watch?
Plan workouts can go to Apple Watch. pacr also imports runs from Apple Health and Health Connect, and connects to Garmin and WHOOP.
Does the coach talk to me during runs?
Yes. The voice coach speaks your splits and pace while you run.
Is it free?
Yes. pacr is free to use today, apart from event tickets.
Training for a different distance?
Same builder, same rules, different limits.
Build your half marathon plan in the app
Free on iPhone and Android. Answer the questions and pacr writes your plan.