Half marathon training plan for beginners: 12 weeks to 13.1

A half marathon is 13.1 miles. That sounds like a long way from a 3-mile run, and it is, but it is a gap that 12 weeks of steady, mostly easy running can close. This half marathon training plan for beginners is built to get you to the start line healthy and across the finish line, with three runs a week and no track workouts.

Who this plan is for

This plan assumes you can run 3 miles comfortably, without stopping, two or three times a week. Comfortably means you could hold a conversation while you do it. If 3 miles is still a struggle, build that base first with Couch to 5K or the 10K plan for beginners, then come back.

The goal here is to finish, feeling strong, not to hit a time, whatever the average half marathon time says. Once you have one half marathon done, a time goal like our sub-2-hour half marathon plan makes much more sense.

If you have a heart condition, diabetes, a recent injury, or any other health concern, or you have been inactive for a long time, talk to your doctor before you start a plan like this.

How long to train for a half marathon

How long you need depends on where you start:

• You can run 3 miles comfortably: 12 weeks, the full plan below.
• You already run three times a week and your long run is about 6 miles: 8 weeks. Start at week 5 of the plan.
• 3 miles is not comfortable yet: build up to it first, then add the 12 weeks.

Twelve weeks is long enough to raise your long run from 4 to 10 miles in small steps, include two easier weeks for recovery, and finish with a proper taper. Squeezing that into less time means bigger weekly jumps and no room for an easier week or a missed one.

The 12-week half marathon training plan

All runs are in miles. Run at an easy, conversational pace unless the notes say otherwise. Tuesday, Thursday and Sunday are suggestions: any three days work, but try not to put the long run the day after another run.

Strides are 4 relaxed accelerations of about 20 seconds at the end of an easy run, walking or jogging back between them. They are not sprints. They remind your legs how to move a little faster without adding fatigue.

Optional cross-training: on one non-running day you can add 30 to 45 minutes of cycling, swimming or the elliptical. Keep it easy. Keep at least one day a week completely off.

How the plan is built

Mostly easy running

Almost every mile in this plan is easy. That is deliberate. In a review of how successful endurance athletes train, exercise physiologist Stephen Seiler noted that studies of nationally and internationally competitive athletes keep finding about 80% of training sessions at low intensity, with hard work kept to about 20%. Those athletes train 10 to 13 times a week and are nothing like beginners, but the logic carries over: easy running builds the endurance a half marathon needs while leaving you fresh enough to keep showing up.

To check your effort, use the talk test. At a moderate effort you can talk, but not sing; if you can't say more than a few words without pausing for breath, you are working vigorously. Your easy runs should sit firmly in the "can talk" zone. If that means slowing down a lot, or taking walk breaks, do it.

Small steps in weekly mileage

The plan goes from 10 miles in week 1 to 19 miles in week 10. Most weeks add 1 or 2 miles, and after each easier week the mileage picks up just above where it was before the break (16 miles in week 7, 18 in week 9), not from the lower number.

You have probably heard the "10% rule": don't add more than 10% to your weekly mileage. Cleveland Clinic calls it a general rule of thumb, and physical therapist Monica Betchker notes there that it can be adjusted to how well conditioned you are and your current mileage. The research is less tidy than the rule. In a randomized trial of 532 novice runners training for a 4-mile race, a slower 13-week program built on the 10% rule produced about the same injury rate as a standard 8-week program (20.8% vs 20.3%). A study that gave GPS watches to 874 new runners found a higher rate of some distance-related overuse injuries, such as runner's knee and shin splints, among those who increased weekly distance by more than 30% than among those who added less than 10%. That result was not statistically significant, and the authors called for randomized trials to confirm it.

The practical takeaway: steady, modest increases are sensible, big jumps are where trouble may start, and no single percentage is magic. Listen to your body more than to the spreadsheet.

Easier weeks

Weeks 4 and 8 drop back to a lighter load. They are part of the training, not a break from it. If you feel great in week 4, run the easier week anyway: that is how you stay feeling great in week 9.

The long run

The Sunday long run is the most important session of the week. It grows by about a mile at a time to a peak of 10 miles in week 10. Run it slowly, at the same conversational effort as your other runs. Finishing a long run feeling like you could have kept going is the goal, not a sign you went too easy.

Use the long runs from week 6 on as dress rehearsals: the shoes, socks, shorts and breakfast you plan to use on race day. Practice drinking on the run, and if you plan to use gels or chews in the race, try them in training first. Our guide to what to eat before a half marathon covers the night before and race morning.

The taper

The last two weeks cut your running back so you arrive at the start rested. A meta-analysis of tapering studies in competitive athletes found the most effective approach was a taper of about two weeks, with training volume cut by 41% to 60% while intensity and how often you train stayed the same. That is the shape of weeks 11 and 12: you still run on the same days and still do your strides, but there is much less of it. Week 11 is 13 miles and week 12 is 5 plus the race, so across the two taper weeks you average about half of your 19-mile peak.

The hardest part of a taper is mental. You will feel restless and may worry you are losing fitness. Two lighter weeks won't undo three months of training. Don't add an extra long run to calm your nerves.

The 8-week option

If you already run about three times a week and can run 6 miles comfortably, you don't need the first four weeks. Start at week 5 and follow the plan from there: that is 8 weeks to race day, with one easier week (week 8) and the same two-week taper.

Be honest with yourself before you skip ahead. If 6 miles leaves you wiped out for days, or you have only run that far once, take the full 12 weeks.

Race day

Your first half marathon should feel easy for the first few miles. That is the trap: race-day excitement makes almost everyone start too fast. Run the first 3 miles at the same conversational effort as your long runs, even if people stream past you. You may well pass some of them in the second half.

A few things that help:

• Pick a pace from your training, not from hope. Look at your average pace on your last few long runs; that is close to a realistic starting pace. Our half marathon pace chart shows what different paces mean for your finish time.
• Use the water stations. Take a few sips at most of them, as you practiced in training.
• Walk breaks are allowed. If you trained with planned walk breaks, keep using them. Taking them early and on schedule works better than waiting until you have to. Our guide to the run-walk method explains how to set your intervals.
• Nothing new on race day. No new shoes, new breakfast or new gel.

Pain is different from tiredness. If something hurts sharply, gets worse as you run, or makes you change your stride, stop and walk, and see a doctor or physical therapist if it doesn't settle. That applies in training, too: a few missed days are much better than a missed race.

If you miss a week

Life happens. If you miss a few days, pick up where you are in the plan and skip the missed runs rather than cramming them in. If you miss a full week or more because of illness or injury, repeat the last week you completed before moving on. With a 12-week plan there is room to slide back a week and still make it to the start line.