How to Prepare for a Half Marathon in 15 Weeks – In-Depth Guide

Do you know how to prepare for a half marathon in 15 weeks?

Half marathon training isn’t a walk in the park. You need to be resilient and patient to see results.

In the 15-week road you have, you’ll encounter pain, soreness, and muscle burning. But the moment your feet hit the ground in front of the finish line and your body gets across it, the sense of achievement will stay forever.

Let’s see what half marathon training in 15 weeks looks like!

How to Prepare for a Half Marathon in 15 Weeks – Training Plan

For a half marathon, 15 weeks may not seem like enough time. It’s true that it’s not all the time in the world, but three months+ are more than enough to make a difference. Here are detailed instructions for each month of your training program until the marathon day.

The First Four Weeks

Contrary to common belief, the first four weeks of your half marathon training plan aren’t the easiest. They may be the most vital part of your plan because they’ll build the running base that’ll keep you going.

You need to be in your best form, avoiding injury at all costs because it’ll take a lot out of you before you even start your 15-week journey.

Running Workouts

In the first four weeks of your plan, you should run at least four days a week. You should do regular running workouts for three days and a long run for the last day.

The regular workouts can be anything that makes you comfortable, whether it’s a tempo run, interval training, or hill training. Start with 1–2 miles and keep increasing your weekly mileage as you go on.

The long-run session should cover more miles since you’ll be doing easy running. Maybe start with 4–5 miles and aim higher.

Strength Training

How to Prepare for a Half Marathon in 15 Weeks:Strength Training

Strength training can take multiple forms. People mostly associate it with weight lifting, but you can ditch the lifting if you’d like. Yoga, for example, is one form of strength training. If you feel more comfortable doing it, then by all means.

In the first four weeks of your half marathon training, you need to dedicate a day a week to strength training.

Strength training is absolutely essential to keep your body well-balanced after all the running you do. Remember that running is purely cardio. It’ll eventually start burning your muscle mass if you don’t grow new ones. That’s when strength training comes into play.


Rest is vital for muscle recovery. If you work out every day, you’ll burn out by the second month, and your plan still has some weeks into it.

In the first month, you can have three days of rest a week. If you’re already a veteran runner and three days is a lot for you, you can do some cross-training and rest for only two days.

The 5–8 Weeks

In the second four weeks of your half marathon training, you won’t make a lot of changes to your half marathon training plan. You’ll still have three days of running, one day of long-running, one day of cross-training, and two days of resting.

The only difference is that you’ll increase your weekly mileage.

Running Workouts

By the second month of your plan, your running workouts should cover more distance, but gradually and gently. You should aim to cover 5–6 miles, depending on your current fitness level. You don’t need to increase your weekly mileage significantly—that’ll have to wait until next month.

The running workouts will stay the same—three days of regular workouts and one day of long-running at a slow pace.

Each week, your long run should increase half a mile or a couple of miles.


By the second four weeks, you should start incorporating cross-training into your weekly schedule. Instead of yoga or weight lifting, you can start adding some low-impact workouts.

Cycling is an excellent choice for runners because it builds leg muscles and focuses mainly on the lower body. Swimming comes in second place because it engages all the body muscles, focusing explicitly on the core muscle group.

Along with cross-training, you may want to start some exercises that’ll strengthen your muscles. These include lunges, squats, and maybe deadlifts.

The 9–12 Weeks

In the third month of your half marathon training, you’ll be closing in on the race. You’ll need to increase the intensity of your running workouts and do your best to avoid injuries. In this phase, rest is most vital.

Running Workouts

By the third month, your regular workout days should have higher mileage. You should be covering 5-6 miles in each run, going at your own pace.

As for the long runs, they should be rising up to 8–9 miles, depending on your fitness level and goal pace.

Contrary to the previous month, you should constantly be increasing your weekly mileage in the third month. You should aim so that the last run of the month is the longest, covering around 15-18 miles.

Bear in mind that this should be the longest run in your whole half marathon training plan. After that run, you’ll begin gradually reducing your mileage or keeping it constant. A half marathon race is a 13.1-mile distance, so you only need to run 15–18 miles once to make sure you can, then start going down to the marathon distance again.


Cross-training stays the same for the third month. Whether you’re cycling, swimming, or lifting weight, keep doing it at a low impact intensity once a week. You can also get in some gentle yoga exercises on your rest days to stretch your muscles.

The 13–15 Weeks

Now, you’re in the last month of your half marathon training plan. You no longer need to add even a single mile to your workout. On the contrary, you should start reducing your mileage by 25% every week.

That way, your body recovers until the race. You don’t have to worry about running the half marathon. Remember that you already covered more than 13.1 miles in your long runs, so you should be able to run the half marathon fine.

Running Workouts

In the last few weeks before the half marathon, you should be reducing your mileage each week. On the 13th week, only run seven or six miles. Reduce it to four the next week, and only run three miles in the week before the half marathon.

As for the long runs, they should be around 8–9 miles long.

Bear in mind that you should only be reducing the distance, but the intensity of your workouts should stay the same. So, don’t slow down; keep the pace normal.

Cross Training/Rest

You’ll want to go easy on the cross-training in the last few weeks. If your body is getting tired from all the running, you may have three rest days and ditch the cross-training. However, it’s better to keep doing it at a lower intensity than the past few weeks.

The 15th Week

When you only have one week until the half marathon, you want to fuel up on healthy food, eat enough, and have a good night’s sleep.

Reduce your daily runs to two or three miles, and keep an easy pace. At this point, your body will have already built its endurance and speed. Nothing you do this week will change your muscle mass or change the way you run.

You’ve been training for a long time, and you’re ready. The biggest challenge to overcome this week is the negative thoughts that’ll keep plaguing your mind. Focus on your goal and have enough rest.

Make sure not to try anything new, be it cuisine, exercise, or even a pair of shoes. Wear the same clothes and only eat healthily. You never know where the wrong move may come from.

Tips for Your Half Marathon Training Schedule

Now that we’re done with the plan, let me show you some tips for the training phase. If you’re a beginner runner, the tips will give you an idea of how you should be preparing for the marathon other than training.

Pay Generously for Your Running Gear

Running Shoes

If you can, allocate a high budget for your running gear. Paying for your shoes and attire is more important than paying for training equipment because you can train out in nature without using anything.

Your running shoe will dictate pretty much everything about your marathon. They’ll determine whether you’re comfortable running and whether you’ll feel pain. Both aspects can make or break your half marathon.

So, my recommendation is to pay generously for a pair of new running shoes and make sure they’re of high quality. Your wallet won’t be happy, but you’ll thank me later when you can run 13.1 miles without getting blisters.

It’s also worth noting that the shoes you train in should be the ones you run the half marathon in.

Decide What You’ll Eat on the Race Day


On race day, you should be fueling up on carbs to store energy for the run. You should also be drinking moderate amounts of water; you don’t want to race while constantly having the need to pee. And chances are, you’re already well-hydrated in your preparation for the marathon.

In those 15 weeks, try to choose random days when you eat what you intend to eat on the race day. Then, train normally and see if the food is good for you.

If you don’t feel fatigued or exhausted after, you’re good to go.

If your energy drains out before you’re done training, you’ll need to choose some other food to eat on the marathon day.

This practice is essential because you don’t want to be eating something for the first time on your race day.

Give Yourself Enough Time to Recover

Recovering isn’t any less important than the actual training. Without a sufficient recovery time, you’ll be stressing your muscles.

You can choose to recover by resting, walking at a moderate pace, or using foam rollers. You can even sleep well, and it’ll do the trick.

What’s important is you should leave enough time for recovery, and don’t do high-intensity exercises on two consecutive days.

By doing so, you’ll make sure your muscles are in good shape for the race.

Final Thoughts On How to Prepare for a Half Marathon in 15 Weeks

A half marathon is 13.1 miles, which is a big deal for most beginner runners. However, I don’t want you to forget that you have 15 weeks until the big day, and that’s a whole lot of time!

As long as you have your training plan ready, your mind in focus, and your running gear in your closet, there’s nothing to fear.

You’ve been running at least two days a week for the past four months, so you shouldn’t be worried much. Besides, your speed doesn’t matter. Even if you’re the last to finish the marathon, the sense of achievement that hits you when you cross that finish line is hard to match!