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The half marathon remains one of the most popular distances in running. It offers a serious test of endurance while asking far less in training and recovery than a full marathon. Still, it isn't a distance to underestimate, since 13.1 miles will expose any gaps in your preparation before you reach the finish.
So if you've signed up for a half and you're not sure you're ready, this article is here to help. If most of the statements below describe you, you can line up to run 13.1 with confidence.
1. You've set a realistic goal and know your "why"
Preparation starts with a goal that fits your experience. For a first half, finishing proud is a worthwhile target. If you already have plenty of shorter races behind you and train to a structured plan, your goal can be more specific, like a target finish time.
Just as important is knowing why you're doing it. A half asks for months of training, and on the mornings when motivation runs low, a clear reason is what keeps you going. Ask yourself what running this distance means to you and what you want out of it.
That reason should be your own, not one handed to you by friends, social media, or anyone else. Motivation that comes from inside holds up across a long training block, while motivation borrowed from other people tends to fade the first time training gets hard.
2. You've raced shorter distances like a 5K or 10K
A half can be your first official race, and there's no rule that you have to run a 5K or 10K first. Even so, a shorter race beforehand is worth it. It takes less time to prepare for, and it shows you how your body handles a hard, sustained effort.
A 10K and a half have a lot in common. Both are longer efforts that call for real endurance and structured training, and the speed and stamina you build for a 10K become a foundation for the half. That's why many coaches treat the two distances as connected steps.
A shorter race also teaches you how events actually work: the start-line nerves, the pacing, the aid stations, and fueling on the move.
Sorting those out at a 5K or 10K means fewer surprises when you step up to 13.1.
3. You've trained for three to six months, or more
A half takes serious preparation, since covering the distance at a steady pace demands endurance that can only be built gradually. How long you'll need is individual and depends on your starting point.
If you already run regularly and have finished a 10K, a few months of focused training is usually enough.
The same holds if you come from other endurance sports like cycling or swimming and keep an active lifestyle, which gives you an aerobic base to build on.
But if you haven't trained in a long time, or have rarely run with any structure, expect at least six months, and possibly more, to build up safely.
Whatever your timeline, consistency and a gradual build are the core principles. Pushing too hard or setting an "at any cost" deadline is how injuries happen. A healthy progression moves from a few easy miles to a comfortable 5K, then a 10K, then longer runs, before the half itself.
4. You've built up enough training volume
For a first half with no time goal, an average of about 15 to 25 miles (25–40 km) a week is enough, with lower totals on easy recovery weeks.
These are ballpark numbers. A lot depends on your level and the pace of your easy runs, both of which shift your weekly total. Mileage is relative anyway: what feels like too little for one runner is too much for another.
Aim to hold a sensible minimum week after week, but remember that the quality and variety of your training matter as much as the raw mileage. A weekly long run alongside a mix of easy and faster days builds more useful fitness than piling on junk miles.
5. You do your long runs
The long run is the most important session in half-marathon training. It builds the aerobic endurance that carries you to the finish and readies your legs and joints for a sustained effort.
Run it easy, at a conversational effort where you could still talk the whole way. A continuous run of roughly 1.5 to 2 hours sits at the core of any half-marathon plan.
You don't need to cover the full 13.1 in training before your first half. Most plans build the long run to about 10 to 12 miles (16–19 km) and leave the rest for race day.
If you can run 10 to 12 miles without struggling, and still feel able to keep going at the end, your endurance is where it needs to be.
Build the distance gradually rather than jumping to it in a single big week.
6. You've tested your nutrition and gear
Long runs are also where you rehearse the practical side of racing, so use them to learn how your body responds. Notice whether your energy dips after a certain point, and practice taking a gel on the move without breaking stride, then see how well it sits.
Gear deserves the same testing. Wear light, moisture-wicking clothing suited to the forecast, and test the running shoes and socks you'll race in.
Anything you plan to use on race day should be proven in training first, so the day itself holds fewer surprises.
7. Nothing is hurting
Being ready also means being healthy. Ordinary muscle soreness after a hard run is normal and expected. A sharp or nagging pain that changes the way you run is not, and it's a signal to stop and deal with the problem rather than train through it.
A niggle that has bothered you for a week or more is worth looking into now, before it turns into something that costs you the race, like a stress fracture. Strength work and mobility a couple of times a week help here, since stronger muscles and tendons absorb the repeated impact of running and lower your injury risk.
A medical check-up is also worth it if you're over 40, have a family history of heart trouble, or are returning after a long pause or injury. Line up healthy, and you'll be able to enjoy the race you trained for.
If you can tick off most of these, you're ready to line up. If a few are still missing, you now know exactly where to focus in the weeks ahead, whether that's building your long run, holding steadier mileage, or letting a nagging pain settle down. Either way, the half marathon is well within reach with the right preparation.
