How to Choose a 12-Week Half Marathon Training Plan

Twelve weeks is the window most runners actually have. Here's how to pick a plan that fits it, and your life.

The race is on the calendar. It's roughly three months out. Somewhere between signing up and now, the excitement wore off and got replaced by a practical question: what exactly are you supposed to do between now and then?

Search for a plan and the volume of options is the problem. Hal Higdon has five different half marathon programs. Pete Pfitzinger has four. The Hansons have three. There are apps, spreadsheets, PDFs from running clubs, and a coach on Instagram selling a twelve-week block that promises a personal best. Every one of them claims to work, and most of them genuinely do work for somebody. That's exactly what makes choosing hard.

The good news is that the twelve-week window narrows the field considerably, and not in the way most people expect. It rules out some of the most famous programs in running, and it makes a few others fit almost perfectly. Understanding why is most of the work.

This guide covers the plans worth considering for a twelve-week half, what each one actually asks of you, and how to match one to the life you're currently living. For the principles underneath any good plan (the intensity distribution, the periodization, the recovery) start with what the research says about half marathon training. This is the layer on top of that: which specific plan, and why.

Before You Pick: Four Questions

Answer these honestly before you open a single training schedule. Your answers do most of the choosing for you.

What are you running right now?

Not last spring. Not the year you were in good shape. What has your average week looked like over the past month?

This is where the most common and most expensive mistake happens. Twelve-week plans are written for runners who already have a base, and that assumption usually goes unstated. Most of these programs assume you're already running somewhere in the range of 15 to 20 miles a week before week one, and new runners regularly mistake a twelve-week plan for a couch-to-finish-line program. Higdon's Novice 1 is explicit about it: the schedule assumes you can already run three miles, three or four times a week.

If you can't yet, that's useful information rather than a disqualification. It means the first few weeks of your twelve are base-building, and your goal for this race is to finish it comfortably rather than to race it.

How many days can you genuinely commit?

Be pessimistic here. The plan you can follow at 90% beats the plan you follow at 60% and then abandon in week seven.

Three days a week is a real option for the half in a way it isn't for the marathon. Four or five days opens up nearly everything. Six days is where the high-volume programs live, and it's a bigger life commitment than it looks like on paper.

What's the actual goal?

Finishing your first half is a different project from taking four minutes off a time you already own. Both are legitimate. They point to different plans, and picking the plan for the goal you wish you had is a reliable way to get hurt.

What else is happening in the next twelve weeks?

A newborn, a job change, a move, a stretch of travel, a knee that's been talking to you. Training doesn't happen in a vacuum, and total stress is total stress whether it comes from mileage or from everything else. A plan that ignores your circumstances isn't disciplined. It's just brittle.

The Half Is a Threshold Race… Up to a Point

Here's a piece of physiology that changes how you read a training plan, and most plan-selection guides skip it.

Lactate threshold is the pace at which lactate starts accumulating in your blood faster than your body can clear it. It has been the best physiological predictor of distance running performance since Farrell and colleagues established it in 1979, and it matters more as race distance increases. It's also more trainable than VO2max, which tends to plateau after a few years of consistent work while threshold keeps improving. For a twelve-week block, that's encouraging: threshold is the quality most responsive to the time you actually have.

The nuance is that threshold pace corresponds roughly to one-hour race pace. For a runner finishing a half in 1:25, that means the race is run essentially at threshold. For a runner finishing in 2:30, the race is run well below threshold, in territory that looks more like marathon effort, and the limiting factor shifts toward endurance and durability rather than the ability to hold a hard pace.

So the same race is two different physiological problems depending on how fast you cover it. A faster runner gets more return from tempo work and threshold intervals. A first-timer or a 2:30 finisher gets more return from consistent easy volume and a long run that builds steadily. If a plan's structure doesn't match which of those problems you're actually solving, it's the wrong plan even if it's an excellent one.

If This Is Your First Half

The goal is to arrive at the start line healthy and finish feeling like you'd do it again. Speed can wait. What you're building is the aerobic base and the confidence that thirteen miles is a distance your body can cover.

Hal Higdon Novice 1

The default recommendation, and the default for good reason.

Length: 12 weeks Days per week: 4 running, 2 cross-training, 1 strength, 2 off Longest run: 10 miles Cost: Free Where: halhigdon.com

The structure is deliberately simple. Long runs build from three miles to ten over the twelve weeks, then a brief taper, then you cover the remaining 3.1 on race day carried by the taper and the crowd. Cross-training lands on Wednesdays and Saturdays and is treated as recovery, not as extra work. There's no speed work at all.

Why it works: The progression is gentle enough that your body adapts instead of breaking. Four running days fit into most lives without renegotiating anything. And building only to ten miles before a 13.1-mile race is not the gap it appears to be, because the taper and race-day adrenaline reliably cover the difference.

The tradeoff: No tempo runs, no intervals, no pace work. If you finish and immediately want to know how much faster you could have gone, you'll have to find that out in your next block.

Choose this if: It's your first half, you can already run three miles comfortably a few times a week, and finishing healthy is the goal.

Hal Higdon Novice 2

The same gentle philosophy for someone with more running history.

Length: 12 weeks Days per week: 4 running, 1 cross-training, 2 off Longest run: 12 miles Cost: Free Where: halhigdon.com

The long run builds from four miles to twelve in week eleven, then tapers. It's aimed at runners who have some races behind them, possibly including a marathon, but who want a measured approach rather than a demanding one.

Choose this if: You've run halves or fulls before, you're returning after a gap, or you simply want a low-drama block that gets you to the line prepared without dominating your calendar.

If You Have Three Days a Week, and That's It

This is the constraint most training content pretends doesn't exist. It's also completely workable for the half.

Hal Higdon HM3

Higdon's three-day program pairs three runs with two substantial cross-training days.

Length: 12 weeks Days per week: 3 running, 2 cross-training Weekly mileage: Roughly 17 building to 24–25 Cost: Free with the book Where: Hal Higdon's half marathon programs

It reads like an intermediate plan compressed into fewer days, with pace runs and tempo runs included rather than stripped out. The cross-training days do real aerobic work instead of functioning as filler.

Choose this if: Three runs is your honest ceiling, you have access to a bike or a pool for the cross-training days, and you want structure rather than a stripped-down plan.

FIRST / Run Less, Run Faster

The most researched three-day framework in running, developed by Bill Pierce and Scott Murr at the Furman Institute of Running and Scientific Training.

Length: Varies by plan; half marathon schedules included Days per week: 3 running, 2 cross-training (the "3plus2" structure) Cost: Around $18 for the book Where: Runner's World Run Less, Run Faster

Every week contains exactly three runs: track repeats, a tempo run, and a long run. Two aerobic cross-training sessions fill the remaining days. The Furman research found that runners on this structure improved VO2max by an average of 4.2% and lactate threshold running speed by 2.3%, and it remains one of the few programs that has attempted a formal scientific evaluation of its own methodology.

Why it works: For the half specifically, the quality-over-volume trade lands well. Two of the three weekly runs target threshold and speed, which is the machinery the race actually asks for.

The tradeoff, and it's a real one: Every run is hard. There are no easy days — the easy running that would normally aid recovery has been replaced by cross-training. That intensity is exactly what makes the program efficient and also what makes it risky for runners stepping up from a gentler routine. One frequent criticism from coaches is that the plan is marketed toward first-timers while demanding a level of intensity that newer runners often aren't prepared to absorb. Too much, too intense, too soon remains the most common path to a running injury.

Choose this if: You have limited days but solid fitness, you genuinely enjoy hard sessions, and you have a bike, rower, or pool available. Skip it if you're new to structured training or you have an injury history.

If You Want to Run It Well

You've finished a half. You know the distance. Now the question is how fast, and the training changes accordingly. This is where threshold work earns its place.

Hal Higdon Intermediate 1 and 2

Two plans at the same difficulty with different emphases, which Higdon describes as existing in parallel universes.

Length: 12 weeks each Days per week: 5 running Longest run: 12 miles Cost: Free Where: Intermediate 1 and Intermediate 2

Intermediate 1 is the endurance-based version: steady running, long and short, starting around 17 miles across five runs in the first week. Intermediate 2 is the speed-based version, and the difference is one day. Wednesdays become speed work, alternating tempo runs with track intervals, with Saturday pace runs and Sunday long runs building from five to twelve miles.

Choose Intermediate 1 if: You want more volume and structure than the novice plans without adding formal speed work yet.

Choose Intermediate 2 if: You're targeting a specific time and want threshold and interval work in the block. Given what threshold does for half marathon performance, this is the stronger choice for most runners chasing a time.

Pfitzinger, Faster Road Racing

The most demanding option that still fits a twelve-week window.

Length: 12 weeks, plus two post-race recovery weeks Days per week: 5–6, depending on which of the four plans you take Peak mileage: Ranges widely; the commonly published schedules run 46–63 and 61–84 miles per week Longest run: 16 miles on the second tier, with mid-week long runs up to 12 Cost: Around $25 for the book

Pfitzinger builds around lactate threshold and endurance, with medium-long mid-week runs doing much of the volume work. Training paces are set using heart rate reserve rather than a percentage of maximum heart rate, which is a more individualized method and requires you to know your resting heart rate.

Why it works: The threshold emphasis is aimed squarely at what determines half marathon performance, and between the long runs and medium-long runs you develop the durability to finish the last three miles at pace rather than hanging on.

The tradeoff: The volume is significant and the plans are comparatively light on pure speed work. They also assume real fitness at the start — this is not a plan to grow into.

Choose this if: You're already running 35 or more miles a week, you can schedule 60 to 90 minute runs on weekdays, and you're chasing a time that matters to you.

Quick Comparison

Making It Survive Contact With Your Life

Choosing the plan is the easy half. Twelve weeks is long enough for life to interfere at least twice.

Treat it as a guideline, not a contract. Completing roughly 80% of prescribed training will get you to the line in good shape. Missing a run does not undo a month of work, and the runners who spiral after one missed session tend to lose far more to the spiral than to the session.

Protect the long run and one quality session. When the week compresses, those two are what you keep. Everything else can shrink. This is the clearest priority order in half marathon training, and it holds across essentially every program listed above.

Don't pick your plan off your goal time. This is the failure mode coaches see constantly. Setting a target that doesn't match current ability produces a plan that's too hard to follow, which leads to injury and burnout rather than to the time. Being too conservative has a cost too, but it's a much cheaper one. Pick for the fitness you have and let the plan raise it.

Ignore what everyone else is running. Watching training logs scroll past on Strava is a reliable way to talk yourself into mileage you haven't earned. Two runners can arrive at the same finish time from very different weekly volumes, and the one who stayed healthy is the one who ran their own plan.

Watch for the signals that mean back off. Persistent soreness beyond normal post-workout stiffness, an elevated resting heart rate across several days, easy paces that suddenly feel hard, or motivation that's been gone for more than a few days. One extra rest day protects the following three weeks, and knowing when to take a break and when to push through is a skill worth developing before you need it.

Respect the taper. The final week or two cuts volume sharply, and feeling restless is the point. Don't add mileage because your legs suddenly feel good, and don't try to recover missed training in the last ten days. The race week principles that apply to the marathon apply here on a compressed timeline.

The Short Version

If it's your first half, take Higdon Novice 1. It's free, it's proven, and it asks four days a week.

If you have three days and good fitness, take FIRST. If you have three days and you're building, take Higdon HM3.

If you've done this before and want to run it faster, take Higdon Intermediate 2 for the threshold work, or Pfitzinger if you're already running high volume and want the most demanding option that fits the window.

And if you've been circling this decision for two weeks, that's the real problem. A twelve-week block that starts Monday will do more for you than the perfect plan you start in three weeks with nine weeks left. Pick the one that matches the days you actually have, start it, and adjust as you learn what your body says about it.