Half Marathon Training Guide

Training for a half marathon is a big undertaking, but with a solid plan and consistent effort, it’s an achievable goal for most runners.

This guide gives you a complete half marathon training plan built around three to four runs a week. You’ll learn how hard each session should feel, how to work out a realistic race pace, what to do when training doesn’t go to plan, and how to use a 5k and 10k along the way to practise for race day.

Not got a race booked yet? Check out our guide to the best half marathons in the UK for inspiration.

Are you ready to run a half?

Before starting a 12-week half marathon training plan, you should be comfortable running 5k without stopping, ideally three times a week. You don’t need to be fast, but it’s important to have a base level of fitness and be used to running regularly.

If you’re not quite ready to race a half, spend a couple of months building your fitness before starting this plan. Increasing your mileage too quickly usually leads to injury, and nobody wants that!

Take a look at our 10k training plan if you want to tackle a shorter race first.

If you're completely new to running, the NHS Couch to 5k programme is a great place to start. It gradually builds you up from short running and walking intervals to a continuous 5k over nine weeks. You can also check out our guide to getting started with running for more advice.

Your half marathon training guide

The two plans below are tailored to different fitness levels. They include easy runs, longer runs, and some faster sessions, with a few recovery weeks to help you adapt. No matter which plan you follow, most of your training will be at an easy, conversational pace, letting you increase your total volume without putting too much strain on your body.

Feel free to move sessions around to fit your schedule, but always try to leave at least one recovery day between harder runs.

Understanding different types of runs

Both plans include different types of running sessions, each designed to improve a particular aspect of your fitness. Here's what they mean:

Easy runs (Zone 2): Comfortable running at a pace where you can hold a conversation. Most of your training should be at this effort.
Long runs: Longer, easy-paced runs that gradually build your endurance.
Steady runs: Slightly faster than an easy run, but still at a comfortable, sustainable effort.
Tempo runs: Sustained running at a 'comfortably hard' pace that you can maintain for a decent amount of time.
Intervals: Repeated bursts of faster running with slower jogging or walking between each effort to recover.
Fartlek: Swedish for 'speed play', this involves alternating between faster and slower running within the same session, usually based on time rather than distance.
Strides: Short, controlled accelerations of around 15-20 seconds, focusing on running fast but relaxed rather than sprinting.
Race-pace runs: Sessions where you practise running at your intended half marathon pace.
Cross-training: Other forms of exercise, such as cycling, swimming or strength training, that complement your running.

16-week beginner half marathon training plan

This plan is designed for runners who can already complete 5k without stopping and are comfortable running three times a week. It gradually builds endurance, starting with three runs a week and adding an optional fourth run as your fitness improves.

Week	Mon	Tues	Weds	Thurs	Fri	Sat	Sun
1	Rest	5km easy	Rest or cross-train	5km easy	Rest	Rest or cross-train	6km long run
2	Rest	5km easy	Rest or cross-train	5km easy	Rest	Rest or cross-train	7km long run
3	Rest	5km easy	Rest or cross-train	5km easy, including 4 × 20-second strides with 60 seconds easy between	Rest	Optional 3k easy	8km long run
4	Rest	5km easy	Rest or cross-train	5km easy	Rest	Rest or cross-train	6km long run
5	Rest	6km easy	Rest or cross-train	2km easy, 6 × 1 min faster / 2 min easy, then cool down to 6k total	Rest	Optional 3km easy	9km long run
6	Rest	6km easy	Rest or cross-train	2km easy, 2 × 6 min tempo / 3 min easy, then cool down to 6K total	Rest	Optional 3km easy	10km long run
7	Rest	5km easy	Rest or cross-train	4km easy + 4 × 20-second strides	Rest	Rest or cross-train	5km race + 1km easy warm-up and 1km cool-down
8	Rest	7km easy	Rest or cross-train	2km easy, 3 × 5 min tempo / 2 min easy, then cool down to 7km total	Rest	Optional 4km easy	12km long run
9	Rest	8km easy	Rest or cross-train	2km easy, 5 × 3 min at 10km effort / 2 min easy, then cool down to 7km total	Rest	Optional 4km easy	13km long run
10	Rest	8km easy	Rest or cross-train	2km easy, 20 min tempo, then cool down to 8km total	Rest	Optional 5km easy	14km long run
11	Rest	6km easy	Rest or cross-train	5km easy + 4 × 20-second strides	Rest	Rest or cross-train	10km race + easy warm-up and cool-down
12	Rest	8km easy	Rest or cross-train	2km easy, 3 × 8 min steady / 2 min easy, then cool down to 8km total	Rest	Optional 5km easy	16km long run
13	Rest	9km easy	Rest or cross-train	2km easy, 2 × 10 min at controlled half marathon effort / 3 min easy, then cool down to 9km total	Rest	Optional 5km easy	17km long run
14	Rest	9km easy	Rest or cross-train	9km easy, including 4 × 20-second strides	Rest	Optional 6km easy	19km long run
15	Rest	7km easy	Rest or cross-train	2km easy, 2 × 5 min at half marathon effort / 3 min easy, then cool down to 6km total	Rest	Optional 4km easy	10km long run
16	Rest	5km easy	Rest or cross-train	4km easy, including 3 × 20-second strides	Rest	Optional 2km easy shake-out	RACE

TRAINING NOTES: Keep your easy runs and long runs at a fairly slow pace (you should be able to hold a conversation). The faster workouts should feel hard, but not like you’re sprinting. Whether you do the optional fourth run depends on how well you’re handling the training and how you feel on the day; it’s entirely your call.

12-week intermediate half marathon training plan

This one is for runners who can already run 10k comfortably, have an established routine of running four times a week and want to improve their half marathon time. Most runs should still be at an easy effort.

Week	Mon	Tues	Weds	Thurs	Fri	Sat	Sun
1	Rest	8km easy	Rest or cross-train	Intervals: 2km easy, 6 × 400m at 5k pace / 200m easy jog, cool down to 7km total	Rest	5km easy	10km long run
2	Rest	8km easy	Rest or cross-train	Tempo: 2km easy, 3 × 6 min tempo / 2 min easy, cool down to 8km total	Rest	5km easy	12km long run
3	Rest	9km easy	Rest or cross-train	Intervals: 2km easy, 5 × 800m at 10k pace / 2 min easy jog, cool down to 9km total	Rest	6km easy	14km long run
4	Rest	7km easy	Rest or cross-train	6km easy + 4 × 20-second strides	Rest or cross-train	Rest	5km race + 2km easy warm-up and 1km cool-down
5	Rest	9km easy	Rest or cross-train	Hill intervals: 2km easy, 8 × 45 sec uphill at hard but controlled effort / jog downhill, cool down to 8km total	Rest	6km easy	15km long run
6	Rest	10km easy	Rest or cross-train	Tempo: 2km easy, 3 × 8 min tempo / 2 min easy, cool down to 10km total	Rest	6km easy	16km long run
7	Rest	10km easy	Rest or cross-train	Race pace: 2km easy, 2 × 4km at target half marathon pace / 1km easy between, 1km cool-down. 12km total	Rest	6km easy	18km long run
8	Rest	8km easy	Rest or cross-train	6km easy + 4 × 20-second strides	Rest	Rest	10km race + 2km easy warm-up and 1km cool-down
9	Rest	11km easy	Rest or cross-train	Tempo: 2km easy, 25 min continuous tempo, cool down to 10km total	Rest	7km easy	20km long run
10	Rest	11km easy	Rest or cross-train	Fartlek: 2km easy, 6 × 2 min at 10k effort / 2 min easy, cool down to 10km total	Rest	7km easy	22km long run
11	Rest	9km easy	Rest or cross-train	Race pace: 2km easy, 2 × 2km at half marathon pace / 1km easy between, 1km cool-down. 8km total	Rest	5km easy	12km very easy long run
12	Rest	6km easy	Rest or cross-train	5km easy, including 3 × 1 min at half marathon pace / 2 min easy	Rest	3km very easy or rest	RACE

TRAINING NOTES: Keep your long runs easy, and allow yourself to recover properly between repetitions in interval sessions. The 22km peak long run is optional for runners who need more than about 2.5-3 hours to complete it; 18-20km is a solid alternative.

Pace and effort: how fast should you run?

One of the most common mistakes runners make when training for a half marathon is running their easy sessions too fast. It might feel like you’re making more progress, but it’s a recipe for disaster because it increases your risk of injury. Slowing down allows you to build endurance without wearing yourself (and your body!) out before your next session.

Try not to pay too much attention to your pace in the first eight weeks of training. Some days you’ll feel on top of the world; others, your legs will feel like lead, and the weather will affect how a run feels, too. Instead, focus on effort.

How to judge your running effort

The easiest way to judge your effort is the talk test. You can also use a 1-10 scale, where 1 is almost no effort, and 10 is an all-out sprint.

Effort	How it should feel
Easy (3-4/10)	You can comfortably speak in full sentences.
Steady (5-6/10)	Your breathing is quicker but you can still manage short sentences.
Tempo (7/10)	You’re working hard and can only manage a few words at a time.
Hard (8-9/10)	You’re breathing heavily, speaking isn’t really possible.

How to work out your half marathon pace

After you complete your 10k tune-up run (ideally, an actual race), you can use your finishing time to estimate a realistic half marathon target. Multiply your finish time by 2.2 for a rough starting point. So a 60-minute 10k suggests a half time of around 2 hours 12 minutes.

Remember this is only an estimate, and for beginners, it’s worth setting yourself a more conservative target. Your training consistency will also strongly affect your race-day performance.

Half marathon pace chart

Goal finish time	Pace per km	Pace per mile
1:30:00	4:16	6:52
1:40:00	4:44	7:38
1:50:00	5:13	8:23
2:00:00	5:41	9:09
2:10:00	6:10	9:55
2:20:00	6:38	10:41
2:30:00	7:07	11:27
2:40:00	7:35	12:12
2:50:00	8:03	12:58
3:00:00	8:32	13:44

Paces are rounded to the nearest second.

It’s tempting to get carried away at the start of a race and go out too fast, but you’ll often pay for it in the second half. The best thing you can do is plan a race strategy and target time based on your goals and training, then stick to it.

The long run

Arguably, the most important session of the week is your long run. These slower, longer runs build the endurance you’ll need to run 13.1 miles on race day, helping your muscles adapt to longer workouts and improving your body’s ability to use fat and carbs for energy. There’s also a mental component: longer runs prepare you for the challenge of running what is ultimately quite a long distance.

Crucially, your long-run pace should feel easy enough that you could hold a conversation (yes, even if that means running much slower than your target race pace!). The goal is to cover the distance without exhausting yourself, not to simulate the actual race, so save your hardest efforts for your tempo runs and intervals.

As your runs get longer, you’ll need to find a route (or a few routes) where you can keep going for an hour and a half or more without frequent traffic lights or busy pavements interrupting you. These route guides should provide some inspiration:

You’ll also need to start thinking about fuelling, because after about 75 minutes, you’ll probably need extra carbohydrates to keep your energy up. Gels are the most common solution, but other options exist. Check out our running nutrition guide for detailed advice.

Strength training and recovery

Strength training has massive benefits for runners. It helps your body cope with the demands of running, reduces your risk of getting injured, and improves your efficiency. What’s not to love?

You don’t have to spend hours in the gym to see the benefits, either. Two strength sessions a week should be fine, each lasting at least half an hour. Prioritise exercises that strengthen your legs (quads, hamstrings, calves), glutes, and core.

If you haven’t done strength training before, start with bodyweight exercises, maintaining proper form, and build up from there.

Recovery is equally as important (and all too easy to overlook). Everybody needs a slightly different amount of sleep, but as a general rule, aim for 7-9 hours a night, and make sure you’re eating enough to support your training. Protein is crucial for muscle recovery and strength gains; carbs also help keep your body fuelled.

Foam rolling can help sore muscles after a hard session, and ice baths can help too, but I wouldn’t blame you for skipping them!

Fuel for training and race day

Carbohydrates are your main energy source when running, so eating enough is important, especially as your training mileage increases. Before a long run or race, have a familiar, carbohydrate-rich meal, and practise taking on fuel during longer sessions so you know what works for you.

Remember to stay hydrated, and eat a meal containing carbohydrates and protein after sessions to help your body recover.

For more advice, read our guides to running nutrition and hydration.

The benefits of tune-up races

Solo training runs have their place, but they don’t fully prepare you to line up with other runners at a race, manage your pace, and handle race-day nerves. That’s why it’s worth incorporating a few tune-up races into your training plan, especially if you haven’t done many races before.

The plans in this guide include two tune-up races to help you prepare.

Start with a 5k

Your first tune-up race is a 5k, scheduled for week seven of the beginner plan or week four of the intermediate plan. It's a chance to see how your fitness is progressing and practise the practical side of racing.

Find upcoming 5k races here.

Move up to a 10k

The second is a 10k, in week 11 of the beginner plan or week eight of the intermediate plan. If everything goes to plan on the day, your finish time in this race can help you set a realistic half marathon goal.

Browse upcoming 10k races here.

If you can't find a local race that fits your schedule, or you don’t want to pay for another entry, don't worry. You can move your tune-up race forward or back by a week and adjust your training around it, or complete the distance as a solo time trial instead.

Seasonal considerations

Needless to say, the time of year you train can affect your preparation. Our famously unpredictable British weather means you may need to adapt your runs to the conditions, especially if you're training through winter or the peak of summer.

Autumn half marathons (Sept-Nov)

Autumn is one of the best times of year to run a half marathon because the weather is moderate, but you’ll do your longest training runs when summer is at its hottest, which is less ideal. Hot weather often means you’ll run a bit slower, and you’ll need to drink more water than usual. Try to run early in the morning or later in the evening when temperatures are cooler.

Find half marathons in September, October and November.

Winter half marathons (Dec-Feb)

Depending on when your race falls, you'll be training through autumn and winter. Expect shorter days, wet weather, potentially icy conditions, and seasonal illnesses. No matter how tempting, don’t force a run when conditions are unsafe, and avoid trying to make up missed mileage all at once.

Find half marathons in December, January and February.

Spring half marathons (March-May)

Like autumn, spring is another great time to run a half. But it also means you’ll be training through the darkest, coldest parts of winter. Wear reflective clothing and a head torch if you’re out on unlit routes, and if you’re heading off-road, sturdy trail shoes are a must.

Find half marathons in March, April and May.

Summer half marathons (June-Aug)

If your race is in early summer, you’ll mostly train through spring, a great time to run. Conditions are generally mild, and the days finally start to get longer. However, later summer races mean training in hot weather. Choose cooler times of day for your longer runs, adjust your pace if needed, and pay particular attention to hydration.

Find half marathons in June, July and August.

What if you miss a week of training?

We all have lives outside running, so something will inevitably get in the way of training at some point. It isn’t the end of the world. Just make sure you don’t try to cram missed sessions into the following week - here’s what to do instead.

If you miss one or two sessions: Carry on with your plan as normal. You don’t need to make up the lost mileage.
If you miss a week: Consider repeating your last completed week rather than jumping ahead.
If you miss two weeks or more: Ease back into it with shorter, easier runs before rebuilding your mileage. If you’ve missed four weeks, you might need to postpone your race or at least significantly revise your expectations.

If you've stopped running because of an injury, don't rush back to keep up with your schedule. I’ve been guilty of this before, so I know how hard it is to miss sessions, but the last thing you want is to make your injury worse. Pause your training until you’ve seen a physiotherapist for advice.

Race strategy

Here’s how to make sure you’re ready for the start line.

The week before

Your training plan includes a taper, which means reducing your mileage to let your body recover before the race. Keep your remaining runs short and easy, with a few brief efforts at race pace. Trust the plan; you don’t need to cram in extra mileage.

The day before

If possible, keep the day before your race mostly restful, with a short walk or gentle jog if you fancy it. Eat foods you know, sip water throughout the day, lay out your kit the night before, and go to bed early. Many runners struggle to sleep the night before a race, so don't let it stress you out too much; if you’ve slept well over the past week, you’ll be fine.

Race morning

Eat breakfast that you’ve had before your long runs and know works well. Arrive with plenty of time to collect your race number if necessary, drop off your bag and use the toilets. And, of course, warm up properly!

Pacing your half marathon

It’s important to go into the race with a pacing strategy.

Kilometres 1-5: Start conservatively, even if you feel fantastic. Your first few kilometres should feel almost too easy; save your energy for the latter half of the race.
Kilometres 6-16: Focus on maintaining a consistent pace. Don’t waste energy overtaking people who've already overtaken you, and remember to stay fuelled and hydrated.
Kilometres 7-20: If you’re still feeling strong, the final 5k is the time to pick up the pace. Otherwise, concentrate on keeping moving towards the finish.
Final kilometre: Now’s the time to give it your all.

Once you’ve crossed the line, enjoy it! Collect your medal, grab something to eat, and take a moment to appreciate what you’ve achieved. Less than 1% of the UK population runs a half marathon each year, and you’re one of them - well done!

Frequently asked questions

How long does half marathon training take?

Most runners need around 12-16 weeks to train for a half marathon, depending on their fitness when they start. If you can already comfortably run 5k and run a few times a week, a 16-week plan will suit you best. If you regularly run 10k and have a solid fitness base, a 12-week plan will serve you well.

What should my weekly mileage be when training for a half marathon?

Your weekly mileage depends on your experience and where you are in training. Beginners might start at around 15-20km per week, gradually building towards 35-40km. More experienced runners may cover 30-50km per week.

Can I walk during a half marathon?

You absolutely can walk for sections of a half marathon; many people do! Regular walking breaks can help you keep going when you run out of energy, and a run-walk strategy can be especially helpful if you didn’t complete your full training plan. Just make sure you check the race cut-off time beforehand.

What shoes should I wear for a half marathon?

Your running shoes should feel comfortable and suit the terrain you’ll race on. Road running shoes are best for tarmac courses, while off-road courses may require trail shoes with better grip.

If you're an experienced runner chasing a fast time, carbon-plated racing shoes can improve running economy and help you run faster, although they're expensive and don’t suit everyone. Whatever you choose, wear them plenty of times before race day; don’t risk your race by trying something new!

Related guides:

Half Marathon Training Guide

Are you ready to run a half?