For many beginning runners, completing a half marathon is a major goal—and it's a great one! While substantial and definitely challenging, the half marathon distance is also very reasonable, even for beginners.
However, running a half marathon requires dedication and preparation. You should plan to devote plenty of time to your training to avoid injury and have a good overall experience.
So, how long does it take to train for a half marathon? It depends. Your goals, background, and existing training base are all factors that determine how long your half marathon preparation should take.
In this article, we'll answer the following questions:
- How long does it take to train for a half marathon race?
- Should I use a half marathon training plan?
- How much should I expect to train each week when preparing for a half marathon?
How Long Does it Take to Train for a Half Marathon Race?
A half marathon, or 13.1 miles (21 kilometers), is a serious undertaking, even for experienced runners. While 5k and 10k distances can be completed with a very minimal amount of training, we would not suggest attempting the half marathon distance without specific training and a plan to help you build up your mileage safely.
Most half marathon training plans are at least 10 weeks long, and some can be as long as 20 weeks. However, before even starting a training plan, you should build your running base so that you are used to running at least three times a week and can complete a 3-mile (or 5k) run without stopping.
With that rule of thumb in mind, the length of time that you should devote to half marathon training depends on a number of factors, including:
- How much you are currently running
- Your goal for the half marathon
- Your background in endurance sports
We'll look at these factors a little closer and then use a few hypothetical examples to show how long the preparation will take.
Your Current Running Mileage
A big factor in how long it takes to train for a half marathon is your starting point.
While the half marathon is a distance that beginner runners can successfully complete, it shouldn't be underestimated. 13.1 miles is a long way, and you should give your body plenty of time to adapt to the physical demands of covering the distance.
Studies have shown that an average weekly mileage of at least 23 miles will help to lessen the risk of injury while training for a half marathon. Runners who are already covering close to that mileage each week will be able to transition right into a half marathon training plan easily. Those running less each week will need to take more time to gradually build their base mileage, ideally adding just a bit of running time each week.
Your Half Marathon Race Goals
Unsurprisingly, the bigger your goals for your half marathon race, the longer it will take you to prepare to meet them. A runner who aims to run a half marathon at a comfortable pace will not need to train as long as a runner who hopes to push their limit and finish quickly. Taking it even further, a runner whose goals include competing at an elite level and winning races may need to devote years to gradually increasing their speed and stamina.
Your Athletic Background
Your background in running and sports, in general, will also affect the time it takes to train for your first half marathon.
Let's say you have no athletic background and are planning to engage in "couch to half marathon" training. In that case, your preparation will involve first learning the basics of running (check out our Learn to Run article for that) and then gradually and carefully building up your running time and mileage. It will likely take several months for your body to adapt safely to your new routine.
A beginner runner with a modest fitness background, such as someone who played a sport like soccer in high school or regularly does cardio work at the gym, will likely adapt to running quickly. These athletes can start to specifically prepare for a half marathon shortly after they start running and may be ready to race within five or six months.
Finally, those athletes who have competed at an elite level in other endurance sports, like cycling, rowing, or swimming, will likely have a very easy transition to running. These athletes already have very strong aerobic engines from years of training. If they have been running a bit, a few months might be enough time to build up sufficient mileage to complete a good half marathon.
Example Athletes and How Long it Takes Them to Train
By using the following calculator and taking into account your fitness background and half marathon goals, we can determine how long to train for a half marathon:
From the calculator, we get the following suggestions for a few hypothetical runners:
- A beginner runner with no sports background who aims to finish strong should expect to train for at least eight months to be ready for a half marathon.
- A beginner runner with a modest sporting background who just wants to finish should train for at least six months to prepare for a half marathon.
- A new runner with an elite-level sporting background whose goal is to compete for a top finish will likely need at least six months of training to be ready for their half marathon.
Special Concerns For New Runners with Elite Endurance Backgrounds
While new runners who have competed at a high level in other endurance sports often adapt to running quickly and show promising speed, they have unique challenges to overcome.
Usually, these elite athletes will have excellent cardiovascular fitness. However, especially if their original sport is non-weight-bearing, like swimming, their musculoskeletal system (or their joints, tendons, ligaments, and bones) will take longer to adapt to the pounding of running.
It is common to see former elite swimmers begin running and immediately find that they can run far and fast without much cardiovascular effort. These athletes understandably become motivated by their early success, run longer and faster because their superior aerobic fitness allows them to, and then spend a lot of time dealing with injuries. This often happens in triathlon; former elite swimmers like Lucy Charles-Barclay or Lauren Brandon have excellent early success when they add cycling and running to their routine but then spend a few years battling running injuries as their bodies take time to catch up to their cardiovascular engines.
The advice for elite endurance athletes or beginner runners is the same: when in doubt, take more time learning to run, allowing your body to adapt gradually to the load and reducing the risk of injury.
How Many Hours Per Week Do You Need to Train for a Half Marathon Race?
We've talked a bit about how many weeks and months it takes to prepare for a half marathon, but what about the weekly commitment? How many days per week should you expect to train?
For a first-time half marathoner, three to four training sessions each week are enough to get you to the finish line. If your schedule allows, an added day of strength training is a good idea, as that will help you avoid injury and run more efficiently. Altogether, most beginner runners can expect to devote three to six hours of exercise a week to training for the half marathon.
However, many athletes' half-marathon training plans include more days and hours of running than this. More advanced half-marathon runners with ambitious goals are likely to run more days per week, with some longer training runs, than new runners with limited running history.
The actual hours, or mileage, per week of running required for a half marathon varies based on two main factors: your goals and your current fitness level.
Your Goals
Your goals for the half marathon will be a major factor in determining how much you need to train. An athlete aspiring to race as an elite runner, or even win the race, will need to run much more, overall, than someone just aiming to finish the half marathon race.
Elite half marathon runners will often follow a training program that has them running five to six days a week, sometimes with multiple runs on the same day, while incorporating plenty of strength and cross-training. These advanced half marathon training regimens include long runs, speed work, and tempo runs, as well as plenty of easy miles and recovery days.
Beginner runners, on the other hand, who want to cross the finish line feeling good but don't have aggressive time goals, can prepare adequately with much less of a time commitment. For them, three to four days a week of running is a good starting place.
Your Existing Fitness Level
To avoid injury, it's important to take into account your current running fitness and build the training volume very slowly to give the body time to adapt. Plenty of research shows that with each running stride (or each time you land on the ground while running), your body will absorb a load of 2 to 3 times your body weight. This repetitive force can easily lead to injury if you're not careful about gradually building your tolerance to running.
Because of this, a beginner runner starting from scratch will need to begin with much lower weekly mileage than an athlete who has been running regularly for some time. Your best bet, regardless of your fitness level, is to avoid increasing your weekly mileage by any more than 10% per week. In other words, if you're currently running 10 miles a week, next week, try 11 miles. Build your running time slowly and carefully, and you'll be much more likely to finish your half marathon without injury.
Whether you've been running for a while or are just getting started, a good training plan will help you prepare for your best half marathon performance. We have designed half marathon training plans to help beginner runners comfortably finish a half marathon and even reach the finish line in a faster time.
You can look at an example training plan below or get a personalized half marathon training plan for free with our run training app.
Wrap-Up
Training for a half marathon race can be a major commitment, but for most beginner runners, the weekly time required is very manageable. If you're consistent with your training and cautious about increasing mileage and intensity, you should be able to complete a half marathon within six months.
In this article, we discussed:
- The general amount of time it takes to train for a half marathon
- The factors that determine how long it will take to train for a half marathon
- The amount of training per week you should expect to do in preparing for a half marathon
- The importance of gradually building your training
As the old saying goes, "Slow and steady wins the race." Give yourself plenty of time to prepare for a half marathon, and be careful about how much you build your training, and you'll cross that half marathon finish line with a smile!