Where to Start If You Want to Run a Half Marathon

For runners who are looking to push themselves beyond 5Ks or 10Ks but aren’t quite ready to tackle a full marathon, a half-marathon provides a challenging but more attainable distance. As its name implies, a half-marathon is exactly half the distance of a full marathon—13.1 miles, or 21 kilometers.

If this goal is at the top of your to-do list, intelligent training is key. So, what’s the best way to ensure that you cross that half-marathon finish line safely and successfully? That depends on your starting point. Jason Karp, Ph.D., the chief running officer for Run-Fit and author of "Running a Marathon For Dummies," offers different tips for two groups: those who have already logged some mileage and those who are just lacing up their sneakers for the first time.

Tips for First-Time Runners

Respect the distance.

As Karp points out, 13.1 miles is a long way to run, so it’s important to prepare adequately for the distance. "Don’t take a nonchalant approach to the half-marathon," he warns. "Confidence comes from being prepared."

Give yourself plenty of time to ramp up.

If you’re not currently running at all, Karp recommends allowing a full year to prepare for a half-marathon.

Start with a walk/run mix.

If you can’t run continuously without stopping just yet, try alternating between running for one to two minutes and then walking for two to four minutes. As you get more acclimated to the activity, you’ll be able to invert that ratio with more running and fewer walking breaks. 

Join a half-marathon training group.

Many runners like training by themselves, especially if they’re introverts or have constraints on their time. Others prefer to have the camaraderie, support and sense of safety that comes with a group of other runners. "By joining a half-marathon training group, you’ll have a group of people to run with and a coach who will give you a program to follow," notes Karp. Plus, you’ll benefit from the sense of accountability and motivation that comes with having a team of people counting on you.

Tips for People Who Are Already Running

Run a lot.

It may seem obvious, but there’s no way around the fact that running a half-marathon requires a lot of preparation. "Training is the key to running the half-marathon successfully," says Karp. He recommends running at least a few times during the week, in addition to one longer run each week. The specific distances will depend on how much you’ve been running and your level of fitness.

Run long.

You should try to complete as many long runs as possible to prepare for the half-marathon. Karp says your longest run should fall somewhere between 11 and 15 miles. If you’re an advanced runner, you may run longer than 15 miles before the half-marathon. 

Mix up your paces.

If you run at the same pace all the time, you’ll never progress in speed, Karp notes. He recommends incorporating the whole continuum of paces in your half-marathon training. For instance, you might take it slow one day for a longer period of time and then run faster and shorter distances another day. This strategy will help to enhance both speed and endurance.

Strike a healthy balance between training and recovery.

"All the adaptations you make that enable you to run farther and faster occur when you’re not running, so take recovery as seriously as you take your training," says Karp. Run-free days don’t have to mean doing nothing. In fact, building inactive recovery activities including yoga, Pilates, walking and biking can make you stronger in the long run.

Whether you’ve been running for a day or a decade, you can complete a half-marathon—as long as you allow the appropriate amount of time to work up to the distance, use a reputable training program and stick to a specific plan. "Running is all science," notes Karp. "Understanding how to train to get a specific result is key to half-marathon success."