How to Train for a Marathon at Every Level

So you’ve decided to take the plunge and sign up for a marathon. Congrats! When you cross that finish line, you’ll become a member of an elite club. “Only around one percent of the world's population run a marathon,” points out Peloton instructor Becs Gentry, a competitive marathon runner.

There’s a reason why it’s so rare: Marathons are incredibly challenging endurance events that take serious dedication. So how should you prepare for it? We gathered the marathon training info you need to know to get to that starting line feeling ready—and excited—to conquer the course. 

How Long Is a Marathon?

A marathon is 26.2 miles, or about 42 kilometers. The race is based on the legend of the Greek messenger Pheidippides who ran about 25 miles from a battlefield in the town of Marathon to Athens in 490 BC to announce a Greek victory over the invading Persians. According to the History Channel, the modern-day marathon distance is based off of the 26.2 mile course from the 1908 London Olympics, which began in front of Windsor Castle and ended at the Olympic Stadium in front of the royal box. 

How Many Months Do You Need to Train for a Marathon? 

How long it takes to train for a marathon depends on your current fitness level and previous experience as a runner, according to Becs. 

Pretty new to running? You’ll want to slowly work your way up to the marathon distance. “The recommendation for beginners to train for a marathon is about a year,” says Palak Shah, PT, who works with runners as the head of physical therapy services at Luna, an at-home therapy provider. This gives your body time to build cardiovascular endurance and adjust to the demands of the sport gradually so you can decrease your risk of overuse injuries when you’re racking up mileage. 

Once your legs are used to longer runs, most runners will follow a dedicated marathon training program for anywhere from three to six months leading up to the race. Peloton’s marathon training program, available on the Peloton App, is 18 weeks. “How much time you need to train fluctuates based on how your body responds to the training,” Shah says. Less experienced runners typically need more time to prep their bodies, while pros who are used to high mileage can pull off a marathon with a shorter buildup. 

Another important factor to take into consideration? “Your personal time commitment level,” Becs says. If you anticipate your daily life, travel, or work getting in the way of your training, give yourself some extra weeks, so you have a little leeway if you miss a run here or there. 

When Should You Start Marathon Training?

If you’re training for a fall marathon, you’ll want to begin dedicated marathon training three to six months before race day. That could mean starting anytime between March and August, depending on the timing of your race and how long you want to train. For a spring marathon, you’d need to start sometime between September and February. 

If you wait too late to begin training, you might not run as strong as you potentially could on race day. On the other hand, if you stay in marathon training mode all year long, you’re setting yourself up for overtraining. 

What Types of Running Workouts Will You Need to Do?

Each run you do during marathon training has a specific purpose. “Runners need to understand their body, their strength, their limitations, and work on those specifics,” Shah says. That said, most marathon training programs (including Peloton’s) include these four types of running workouts.

Long Run

The weekly long run is just what it sounds like: the run with the most mileage each week. It gradually builds throughout training to get your legs and lungs ready to tackle the marathon distance, and typically peaks at about 20 miles. “Endurance is the key—the long run is the most important,” Becs says. 

Tempo Run

Although there’s some debate on the exact definition of a tempo run, the general idea is to hold a fairly difficult pace for a sustained period of time. Most experts suggest aiming for a comfortably hard effort (about a six out of 10 rate of perceived exertion), or the top speed you could run for an hour straight. These workouts are tough, but they help prep your body (and mind) to maintain the pace you want on race day.

Recovery Run

Recovery runs are sometimes called easy runs because they’re fairly short and done at a slower pace. They help your body bounce back from harder runs faster by getting your blood flowing without putting a ton of stress on your muscles. They also get you ready for what you’ll feel in the later miles of a marathon. “Always do recovery runs to capture your power of running on fatigued legs, which is what endurance running is based off!” Becs says. 

Interval Workout

Interval training asks runners to hit specific intensities for certain amounts of time before they  rest and repeat. That might look like 60 seconds at a 5K pace repeated 10 times with 30 seconds of rest in between, or hitting half marathon pace for one mile and repeating that three or four times. This not only helps increase your speed, but the mental toughness you’ll build will make marathon pace feel more doable on race day. While there are different types of internal runs, common workouts include tempo runs and sprint workouts.

What Should You Eat While Marathon Training? 

When you start racking up serious miles, your diet needs to step up, too. In particular, make sure you’re getting enough carbohydrates and protein, according to dietitian Danielle Crumble Smith, RD. “There's a heavy focus on carbohydrates because that helps with glycogen stores, which is essential,” she says. “But if you’re not consuming adequate protein, then you might end up feeling really tired and not recovering well, breaking down muscle.”

Before your runs, stick with simple, easy-to-digest carbohydrates and maybe a bit of protein. “Those simple carbohydrates break down to sugar more quickly, which is really beneficial during a long run because you want your body to be able to access that glycogen,” Smith says. Meanwhile, having a little protein will help maintain your energy levels longer. That could look like a bagel with some peanut butter and a banana, maybe with a hard-boiled egg or a little Greek yogurt. (Avoid anything high in fiber or fat, both of which can take a while to get through your system.) 

On long runs, it’s also important to eat while you’re running. Most runners need 30 and 60 grams of carbohydrates every 30 to 45 minutes to sustain their energy—that can be accomplished by taking gels, sipping sports drinks, or even eating pretzels or candy. Smith suggests using your weekly long runs to experiment with different kinds of fuel to see how your body responds, well before race day arrives. It can sometimes be hard to take in enough calories without causing GI issues, but it is possible to train your stomach to digest while running just like you’re training your legs.

You’ll want to eat more protein and carbs again after you’re done with your run to refuel. “Have an omelet with avocado toast or a sweet potato hash that has eggs,” Smith suggests. Running long distances can sometimes repress our hunger signals, so if your body doesn’t feel ready to eat right away, Smith suggests drinking a protein shake instead. 

What about carb loading? That happens during the three days before the race. For each meal during that time, “have half of your plate carbohydrates, with a quarter of protein and a quarter of veggies,” Smith suggests. Just make sure the veggies are easier-to-digest options like green beans and zucchini rather than kale or broccoli, so you can hopefully avoid porta-potty stops during the race. 

How Much Cross Training Should You Do? 

When it comes to cross-training during a marathon build up, Shah recommends focusing on building strength, power, control, and stability. “Those are the four most important components that you need to be thinking about,” she says. Strength can be built through traditional strength training exercises like lunges and deadlifts. To build power, plyometrics are your best bet. And workouts like yoga and Pilates can increase your control and stability. In any of these workouts, Shah suggests focusing on the quads, hamstrings, glutes, calves, and core—the muscles that are most challenged in distance running. 

“Ideally, you want to incorporate strength training a couple of times a week and as the intensity of the running program increases, the intensity of the strength sessions will decrease, meaning you will lift lighter,” Becs says. “The same applies to other modalities of cross-training such as cycling or rowing: You decrease the intensity of those as you close in on marathon day.” 

Can You Train for a Marathon on a Treadmill? 

A treadmill like the Peloton Tread gives you an opportunity to control your running environment. That of course means it’s a safe place to run when the weather isn’t cooperating, or you don’t feel comfortable running alone outside. It also means you can have precise control over the pace, Shah points out. “A treadmill allows you to train specific parameters,” she says. This makes it especially helpful for speed work like interval workouts or tempo runs when you want to nail a particular pace.  

“You can do as much training on the treadmill as you need to or want to,” Becs says. That said, your marathon will most likely take place outside, so you should get used to running on a similar surface—whether that’s on asphalt or dirt trails. “Ideally, long runs are done outside,” Becs says, “but sporadically doing them on the tread is better than not doing them!” 

When Should You Start Tapering? 

As you get close to race day, it’s time for what’s called a “taper.” This is the point where you progressively dial back your training so that your body has time to recover from all the fatigue you’ve built up over the past several weeks. 

“This period gives the body time to soak in all the hard work and adaptations it’s made in training to arrive at the start line as strong as possible,” Becs says. Research shows that the ideal taper lasts three weeks—runners who tapered that long finished an average of five minutes and 32 seconds faster than those who followed a short taper. 

During this time, you’ll decrease your volume, or how many miles you’re running. You’ll want to keep doing your interval and tempo runs to keep your legs snappy, but be careful not to overdo the paces since you’ll be feeling fresher. Also: Now that you aren’t running so much, you can use the extra time to focus on recovery techniques like stretching, foam rolling, and Epsom salt baths.

What to Do When Marathon Training Gets Hard

Marathon training can be… a lot. When you’re tempted to throw in the towel, remember: “Everything passes,” Becs says. Each hard interval and each long run will eventually end. Even your whole marathon training plan will finish on race day, and you can let your legs recover afterward for as long as they need. 

In the meantime, keep in mind that you signed up for a marathon not because it’s easy, but because you wanted to challenge yourself. As Becs says, “Hard things change us and we only get tougher by getting through them.”

The truth is that struggling during marathon training means you’re doing exactly what you should be doing to get stronger and faster. So don’t be too hard on yourself. “Be humble and have grace,” Becs says.

That said, if you suspect you’re running more than your body can handle, it might be time to pull back a bit or amp up your recovery efforts. Shah suggests paying to your V02 max stats if you have a smartwatch (it won’t give you an exact measurement, but can give you a general idea). This number tells you the maximum amount of oxygen your body can consume during exercise. “When your VO2 max starts depleting, that could mean you’re overtraining,” she says. 

Train for a Marathon with Peloton’s Training Plan 

Ready to get started? Peloton has you covered with an 18-week marathon training plan, available on the Peloton App. The guided, audio-only runs start at just two to three miles and build up to 20 to get you ready for race day. You’ll get dedicated marathon race prep runs, tempo runs, recovery runs, long runs, and strength classes designed specifically to meet the needs of runners. All the while, the app will track your progress so you can see just how close you’re getting to that finish line.