The half marathon: 10 to 16 weeks, built around your life
Hal Higdon's Novice 1 half marathon program runs 12 weeks, with four runs a week and a long run that grows to 10 miles before race day. Published plans sit either side of that: London Marathon Events publishes free 10-week plans for its Big Half, and run coach Ian Scarrott's PureGym half marathon plans run 16 weeks at every level. The long run is the anchor of the block whichever length you pick.
A half marathon is a serious endurance challenge that requires a couple of months of committed training, without the 18- and 20-mile long runs of a full marathon block, its total-life-takeover mileage, or its deep recovery cost. Three to five runs a week is enough to train for a strong half and still have a life.
How long you need
The scale below is this guide's own, set inside that published 10-to-16-week span; no single program prescribes it.
| Where you are starting | Time to the half | What the block does |
|---|---|---|
| Comfortable 10K already | 10 to 12 weeks | Build to the distance and add race-specific speed. |
| Running regularly, new to longer distances | 12 to 14 weeks | Grow the long run alongside the weekly base. |
| Newer runner on a modest base | 14 to 16 weeks | Let the long run grow without spiking your injury risk. |
The long run is everything
If you get one thing right in half training, make it the long-run progression. This is the run that builds the endurance to keep moving efficiently for the length of a half marathon. Higdon's Novice 1 schedule grows it in one-mile steps with repeats and two tune-up races along the way: 4, 4, 5, 5, 6, a 5K race, 7, 8, a 10K race, 9, 10 miles, then the half itself. Run most of it easy and conversational, at an effort well below race pace. Rushing the long-run build raises injury risk before race day.
The quality sessions that matter for the half
The half is run near your threshold, so threshold work is your bread and butter, complemented by segments at race pace:
- Tempo Run: sustained comfortably-hard effort that raises the pace you can hold for the distance.
- Cruise Intervals: threshold effort in repeats with short recoveries, letting you bank more quality time at pace.
- Half-pace work in the long run: rehearse race effort by finishing part of a long run at goal half-marathon pace.
- Progression Long Run: start easy and gradually lift the pace so the final miles are quicker, training you to stay strong when tired.
Fueling: don't skip it
For exercise lasting more than about 60 minutes at a hard effort, the International Society of Sports Nutrition recommends roughly 30 to 60 grams of carbohydrate per hour, taken as a sports drink or gel, to support performance (Kerksick et al., Journal of the International Society of Sports Nutrition, 2017). Carry that into the half: plan for carbohydrate plus water during the race, and practice on your long runs before race day. Dial in what your stomach tolerates and how frequently you need it, so race day carries less guesswork.
The taper
A meta-analysis of 27 taper studies in competitive athletes concluded that a two-week taper during which training volume is exponentially reduced by 41 to 60%, without modifying training intensity or frequency, "seems to be the most efficient strategy to maximize performance gains" (Bosquet et al., Medicine & Science in Sports & Exercise, 2007). Resist the urge to cram: no long run in the last week will make you fitter, but it can make you tired. Trust the work you've banked.
How Runked's plan works
Training plans are part of the one Runked subscription, which starts with a 7-day free trial on the yearly plan. Choose "train for a race," pick 21.1K half marathon, set your race date and goal time, and the app builds a personalized block around your ability, sessions per week, available days, long-run day and distance, and weekly mileage. The plan is laid out week by week through the app's plan phases: Foundation, Early Quality, Transition, Race Prep, Taper and Recovery; a shorter plan may not use every phase. A clear CURRENT WEEK marker shows where you are, and Manage Plan lets you edit inputs and regenerate when life shifts around.
Race predictions project your finish time for the half and update as your fitness builds, so you can watch your 21.1K readiness improve across the block instead of guessing whether the goal is realistic. Compare to yourself, not to others: in Runked, the running rank depends only on your own running, and so does the projection.
When you get sick or hurt
Sixteen weeks is a long time to stay perfectly healthy. Runked's status selector lets you set Rest, Sick, or Injured to pause the plan, then pick back up as Active when you recover. One disrupted week won't unravel the whole build.
Build your half marathon plan
Runked is free to download, and one subscription covers your rank, GPS tracking, personalized training plans and race predictions: $59.99 a year after a 7-day free trial, or $11.99 a week. That includes the full 21.1K block.
Download on App StoreFrequently asked questions
How long do I need to train for a half marathon?
Hal Higdon's Novice 1 half marathon program runs 12 weeks, with four runs a week. Published plans run shorter and longer than that: London Marathon Events puts out free 10-week plans for its Big Half, and run coach Ian Scarrott's PureGym half marathon plans run 16 weeks at beginner, intermediate and advanced level. Runked builds a personalized block around your race date, available days, long-run day and the weekly mileage you set; it costs $59.99 a year after a 7-day free trial, or $11.99 a week.
Can I train for a half marathon in 8 weeks?
Eight weeks is shorter than any of the published plans on this page, the shortest of which is London Marathon Events' 10-week Big Half plan. With a solid base already in place, such as a comfortable 10K and a weekly long run near 8 miles, eight weeks can sharpen what you have; building the distance from scratch in 8 weeks raises injury risk and a rough race day.
How many miles a week for half marathon training?
Published beginner plans define the week by its sessions and let the mileage follow: Higdon's Novice 1 half schedules four runs a week, with the long run growing from 4 miles to 10 across 12 weeks. In Runked you enter the weekly mileage you want and how fast it should progress, and the block is built around that.
What pace should my long runs be?
Most of your long run should be easy and conversational, clearly slower than goal half pace. As the block progresses you can add segments at half-marathon pace to rehearse race effort, but the bulk stays comfortable to build endurance without excess fatigue.