Getting round your first 13.1 or chasing a new time: Pulsar builds the weeks from where you are, and every run says how far, how fast and why.
On a computer? Scan it with your iPhone camera.
A half marathon is 13.1 miles, 21.1 kilometers. It’s long enough that endurance decides the day, and short enough to train for around work and family. For many runners it’s the race that turns them into distance runners.
The long run is the heart of a half marathon plan. It grows slowly, steps back every fourth week and tops out around 11 to 15 miles, depending on your level. It never goes past two and a half hours on your feet, and you don’t need to run 13.1 before race day.
The key faster session is the tempo run: comfortably hard running that raises the pace you can hold for an hour or more. Intervals appear too, but they play a smaller part than in a 5K or 10K plan.
Pulsar builds the plan from your recent race if you have one, your weekly miles and the days you can train. It recommends at least twelve weeks for a newer runner and ten for a trained one.
I trained for three marathons alone. Pulsar is the coach I wish I’d had.
Four things every Pulsar plan does for you, shown the way they look in the app.
How long can you run without stopping?
An honest answer sets the right starting point — there’s no wrong one.
Pulsar asks how long you can run without stopping, which days you can train and your latest race time, if you have one. Week 1 is built from those answers.
Aerobic Easy
Week 7 · Tuesday Upcoming
4.1 mi · ~45 min
Coach’s insightTap to ask
Keep your heart rate in Zone 1-2. You should be able to hold a conversation easily. If you’re breathing hard, slow down.
Target heart rate
Z1 RecoveryZ2 Aerobic123–148 bpm
Structure
Easymax 10:50 /mi
4.1 miRepeat ×4
Strides7:55 /mi
100 mWalk recovery
1 min Each run carries its distance, the pace to hold, the heart-rate zone to stay in and what it’s for, in plain words.
PULSAR Coach
Why is my easy pace so slow?
Because easy runs do a different job. They build your engine — heart, lungs, legs — without leaving you tired for Thursday’s 400s. If you can talk in full sentences, you’re right where you should be.
AI-generated guidance, not medical advice. Talk to a doctor about health concerns.
After every run, a short note on what it meant, with your numbers. Between runs, ask about pace, fueling or a missed week.
The voice coach, in your earbuds: “Slow down, 20 seconds fast.”
Voice cues in your earbuds when a tempo or interval drifts off pace, and the whole workout on Apple Watch, with or without your phone.
Two runners, two half marathon plans, both built by the app. Switch between them to see how the weeks change with the starting point.
Built for an occasional runner doing about 9 miles a week with no race yet, three days a week, aiming to finish. Miles per week as the app built them, race week without the 13.1-mile race; yours are built from your goal, your days and how you run today.
Built for a 55:30 10K runner aiming at 2:00:00, four days a week, long run on Sunday. Miles per week as the app built them, race week without the 13.1-mile race; yours are built from your goal, your days and how you run today.
Four steps from here to the start line.
It’s free to download on iPhone. Your plan lives on the phone, and on Apple Watch if you wear one.
A race and its date, a distance, a time to beat, or running without stopping. Then how you run today.
Open today’s run and start it. Pulsar gives you the pace and the zone, and talks you through every segment.
The plan builds week by week, then eases off before race day so you arrive fresh, not tired.
Every session has a job. These are real workouts from the two plans above, laid out the way the app shows them.
Easy run
Aerobic Easy
Week 9 · Tuesday
4.0 mi · 50–56 min
Structure
Easymax 11:40 /mi
3.8 miRepeat ×4
Strides8:25 /mi
100 mWalk recovery
1 minMost of your week: easy enough to talk the whole way, with four short pickups at the end to keep your stride quick.
Easy run
Recovery Easy
Week 5 · Saturday
1.8 mi · 21–24 min
Structure
Easy runmax 11:25 /mi
1.8 miShort and very easy, next to a hard day. It keeps you moving without adding load.
Tempo
Progression Tempo
Week 5 · Thursday
4.0 mi · 45–50 min
Structure
Warm upmax 11:55 /mi
1.2 miMarathon pace10:10 /mi
0.8 miThreshold9:30 /mi
0.7 miCool downmax 11:55 /mi
1.2 miWarm up, then a stretch at marathon pace that steps up to tempo pace. Two gears in one run.
Tempo
Tempo Sandwich
Week 7 · Thursday
2.8 mi · 30–33 min
Structure
Easymax 11:50 /mi
0.9 miThreshold9:25 /mi
1.1 miEasymax 11:50 /mi
0.9 miEasy, a mile at tempo pace, easy again. A gentle way into tempo running early in the build.
Tempo
Threshold Ladder
Week 9 · Thursday
5.5 mi · 59–65 min
Structure
Warm upmax 11:40 /mi
1.2 miThreshold9:25 /mi
600 mWalk recovery
40 secThreshold9:25 /mi
900 mWalk recovery
1 min 5 secThreshold9:25 /mi
0.9 miWalk recovery
1 min 35 secThreshold9:25 /mi
900 mWalk recovery
1 min 5 secThreshold9:25 /mi
600 mCool downmax 11:40 /mi
1.2 miUp and down the ladder at tempo pace, with short walks between. More time at tempo pace than one block would allow.
Tempo
Classic Tempo
Week 11 · Thursday
4.8 mi · 50–56 min
Structure
Warm upmax 11:30 /mi
1.2 miThreshold9:15 /mi
2.3 miCool downmax 11:30 /mi
1.2 miThe key half marathon session: over two miles at tempo pace. Comfortably hard: short phrases, not full sentences.
Intervals
Long Reps
Week 12 · Thursday
3.7 mi · 40–44 min
Structure
Warm upmax 11:30 /mi
1.2 miRepeat ×2
5K pace8:20 /mi
800 mWalk recovery
3 min 5 secCool downmax 11:30 /mi
1.2 miTwo 800s at 5K pace. In a half plan intervals play a supporting part, keeping some speed in your legs.
Long run
Fast-Finish Long Run
Week 12 · Sunday
11.2 mi · 127–140 min
Structure
Easymax 11:30 /mi
9.9 miFast finish — steady9:45 /mi
1.2 miThe longest run of the first-half plan: ten miles easy, the last one steady. You don’t need to run 13.1 before race day.
It depends on where you start. If your date is too close, Pulsar says so before it builds the plan and suggests a target you can reach.
Can’t run nonstop yet
12 weeks or more
Run/walk first, then the half marathon build. With less time, Pulsar suggests a shorter race first.
Newer runner
12 weeks or more
Pulsar recommends at least twelve weeks for a newer runner. Fourteen to sixteen is more comfortable.
Trained runner
10 weeks or more
Ten weeks is enough if you already run regularly and your long run is over an hour.
What matters around the runs: what to eat, how to pace the race, how to recover. The coach in the app answers the rest.
Half marathon training is where fueling starts to matter. On runs longer than about 75 to 90 minutes, most runners feel better with some carbohydrate on the way.
Race morning: a familiar breakfast of about 300 to 500 calories, two to three hours before the start, low in fat and fiber. Use the same gels you trained with, at the same times. Nothing new on race day.
Thirteen miles is a long time to hold your form. Two short strength sessions a week work the muscles that carry you through the last miles: squats, lunges, single-leg calf raises, hip bridges and a plank. Twenty to thirty minutes, on easy days. The evidence that strength work prevents injuries is mixed, so it’s a useful extra rather than a requirement.
Cross-training builds aerobic fitness without extra impact. A bike ride or a swim can replace an easy run in a week when your legs feel heavy, but not the long run or the tempo run.
The half marathon rewards patience. The pace that feels easy in mile 2 decides how mile 11 feels.
Pick the pace from your training. Pulsar predicts your half marathon time from your runs, and the tempo runs tell you how a pace feels. On hills or on a hot day, run by effort and let the pace go.
Form is what slips first when you get tired, and in a half marathon you will be. Keep these in mind on your long runs:
Pick one cue per long run. By race day they’ll be habits, not thoughts.
Long runs are the sessions your body takes longest to absorb. What helps:
Pain that is sharp, gets worse as you run or changes how you run is a reason to stop and see a doctor or a physical therapist, not something to run through. Pulsar’s coach will tell you the same.
Rehearse your race kit on a long run a few weeks out: the shoes, the socks, the shorts and the gels. On the day, wear nothing new.
The rules every plan keeps. They’re the same rules the coach explains when you ask why.
Mostly easy
About four-fifths of your running is easy enough to talk through, and Pulsar leans more careful than that on purpose. Easy running builds the engine; the hard sessions only work on top of it.
Every fourth week lighter
Three weeks of building, then a lighter week at about 80 percent so your legs catch up. The week after picks up where the build left off, not beyond it.
A little more each week
Weekly mileage grows by about 7.5 percent for newer runners and 10 percent for trained ones, with a cap on any single jump. Hard days never land back to back.
Paces from today’s fitness
Your paces are worked out from your recent race or how you run now, never from your goal, and they move week by week as the plan goes on.
Long runs have a time limit
In a half marathon plan the long run stops at 2 hours 30 minutes. For a slower runner that comes before the distance limit does, and that’s intended.
Easier at the end
The last two weeks cut the miles by 40 to 50 percent and keep the pace, so your legs are fresh for all 13.1.
A half marathon is 13.1 miles, or 21.1 kilometers: exactly half a marathon.
Twelve weeks or more if you’re newer to running, ten if you already train regularly. Fourteen to sixteen weeks is comfortable for a first half. The two example plans on this page are fourteen weeks each.
Yes, with enough time. If you can already run for 30 minutes, Pulsar recommends at least twelve weeks. If you can’t run nonstop yet, Pulsar starts with run/walk, and it will suggest a shorter race first if your date leaves fewer than twelve weeks.
For most first-timers, 10 to 12 miles. Pulsar caps the long run at 2 hours 30 minutes, and you don’t need to run the full 13.1 before race day. In the first-half plan on this page, the longest run is 11.2 miles.
If you’ll be running for more than about 75 to 90 minutes, take some carbohydrate on the way, starting around 45 minutes in. Use what you practiced on your long runs, and drink to thirst.
Three is enough to finish a half; four or five helps you run it faster. Pulsar builds plans on 2 to 7 days a week and lets you choose the days and your long-run day.
More easy miles, a long run that builds past 11 miles, and a weekly tempo run. In the last weeks, some plans put stretches of half marathon pace into the long run itself.
Yes. Plenty of runners use planned walk breaks, and research on run/walk in long races hasn’t shown it costs much time. Decide before the race, and practice it on long runs.
Give yourself at least 16 weeks, keep building your weekly miles and let the long run grow toward 20 miles or three and a half hours, whichever comes first. The marathon plan does exactly that.