This Is What It Actually Takes to Run a Marathon

Woman running a marathon

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If running a marathon is one of your dreams, we are here to help you check that off your bucket list. A marathon is a long-distance race in which you run 26.2 miles in one day. Yes, it does sound intimidating, but with the right training program, it is a goal you can absolutely achieve. It takes on average between four and five hours to complete the race, although some elite athletes finish in two hours—and it takes some people much longer. Regardless of how long it takes you to finish, you are set with bragging rights for life.

To prevent injuries and help you perform your best, it is essential to give yourself plenty of time to train. “A 15- to 16-week marathon training plan tends to be the sweet spot for many runners,” says Thomas Watson, certified running coach and founder of Marathon Handbook.

“It's sufficient time to adapt to longer runs—without being so long that the runner is doing an excessive amount of high-mileage weeks increases the risk of injury and exhaustion," he says.

Meet the Expert

  • Thomas Watson is an ultra-runner, UESCA-certified running coach, and founder of Marathon Handbook. He is the author of several books, including Marathon In Three Months: How To Train For A Marathon In Twelve Weeks and The Four Hour Marathon.

Ready to get started?  Check out our 15-Week Marathon Training Plan to help you reach (and yes, even exceed!) your running goals. 

Marathon Training Length

Before you sign up for a marathon, make sure you plan far enough out that you have time to build up your running endurance. The 15-16 week timeframe is ideal; however, depending on your starting fitness level, it may take more or less time.

“I tend to recommend that first-time marathon runners spend around 16 weeks getting marathon ready,” Watson says. “If the runner doesn't have much of a background in distance running, we spend five or six months on it, with the first couple of months being all about building up the running base. Experienced distance runners can tune in their training and get ready in as little as 10-12 weeks.”

You also need to consider your goals when determining your training time, says Buckingham. “If the goal is just to finish, a shorter build-up can be implemented. However, if the goal is to run a personal record or hit a certain time goal, then a runner could benefit from a longer build-up.”

Benefits of Running a Marathon

mixed femme running


There are many benefits to training and running a marathon. A recent study in the Journal of the American College of Cardiology found that training for a marathon for the first time takes four years off of your cardiovascular age. In particular, they found that that training portion, in which you train for several months, running six to 13 miles per week, reduces blood pressure and aortic stiffness. 

“Running is one of the best things you can do for your health,” says Buckingham. “If running could be bottled up and sold in pill form, it would be the most widely prescribed medicine in the world for the numerous health benefits.”

In addition to the cardiovascular benefits, Buckingham says running has several more benefits, including decreased risk of Alzheimer's, diabetes, certain types of cancer, and obesity, as well as improved metabolism and mood.

Despite these benefits, you must check in with your doctor to make sure you get the green light for marathon training. In particular, people who have high blood pressure, heart conditions, arthritis, or musculoskeletal injuries should talk to their doctor before starting a marathon training program.

What to Eat When Training

It is imperative that you have a well-rounded diet when training for a marathon; however, Buckingham says it is essential to pay attention to your carbohydrates and protein intake.

“Carbohydrates are the body’s main source of energy while running,” he says. “The body can only store about 2000 calories (or around two hours) worth of energy in the form of carbohydrates. So, every time you go for a run, you’re depleting your carbohydrate stores.”

He says to make sure you are eating plenty of healthy sources of carbohydrates, including whole grains, fruits, and vegetables. “Because none of us can run a marathon under two hours, we will need supplemental carbohydrates to get us through the race. Consuming energy gels during your long runs is an important component.”

Energy gels come in small 1-ounce or 1.5-ounce packets and contain the right amount of carbohydrates to maintain energy and prevent fatigue while running. If you run for more than 60 minutes, you should consume energy gels regularly to perform your best.

In addition to carbs, he says to make sure you are eating plenty of high-quality sources of protein, such as fish, poultry, Greek yogurt, beans,` and tofu. “Protein is another crucial nutrient for the body during marathon training. While we don’t use much protein for energy during our running, it is vital for recovery following a run,” he says. “Protein is the building block of muscle, so it is extremely important to consume enough protein during your marathon training.”

Buckingham explains that running causes small microtears in the muscle, and the role of protein is to repair the muscle damage and build the muscles up stronger, so it doesn’t cause as much damage the next time.

Follow these nutrition tips throughout your training program—and make sure you do not try new foods, energy gels, or drinks on the day of the race. "It would be a shame if you got to mile 20 and started having GI distress because you ate a gel on course that you hadn’t tried before. A little planning goes a long way!”

Equipment for Marathon Running

person running down stairs at sunset


“The great thing about running is that you don’t need much equipment to get started. A good pair of running shoes is all you need!” says Buckingham.

It is essential that you find the right type of running shoe that fits your foot to prevent problems including blisters, sore toes, and bruised toenails. You may want to consider getting a fitting at a shoe store that specializes in running shoes. In general, the American College of Sports Medicine (ACSM) says to make sure you have at least ½ inch of room between the front of your shoe and your toes. A good rule of thumb is that there should be enough space to place your thumb between the front of your shoe and your big toe. Your shoe should also be wide enough that you can wiggle your toes easily.

The ACSM says that it takes several weeks to break in a new pair of running shoes. Do not buy a new pair to wear on marathon day, as it may result in pain and blisters.

Buckingham says that in addition to shoes, you will also need proper running attire. “As you become more invested in your marathon journey, you will likely invest in sweat-wicking socks, dri-fit shirts, specialized shorts that have a built-in pocket for your keys, and a nice pair of sunglasses to block the sun—or hide the tears in your eyes at mile 22…not that I’m speaking from personal experience or anything!”

Lastly, make sure you train with the same shoes and outfit you will use on the marathon day. “On the day of the marathon, make sure you have your race outfit and make sure that you’ve tried this outfit prior to race day,” he says.

“Rule number one of marathon running: Never try anything new on race day," says Buckingham. "That includes shoes, socks, shorts, shirts, underwear, gloves, and arm/calf sleeves. The most calming and comforting thing you can do for the day of the marathon is to ensure that you have tried everything beforehand and you know that it will work for you.”

15-Week Marathon Training Plan

The following training plan, developed by Watson, will ensure that you have the endurance, strength, and preparation to run a marathon.  “My general approach to a marathon training weekly schedule—especially for first-time runners—is four days of running, one day of strength/cross-training, and two rest days,” he says.

He recommends shorter training runs on Tuesday, Wednesday, and Friday, with your longer run on Sunday. Thursday is your strength/cross-training day, while Monday and Saturday are your rest days. Of course, you can alter this schedule as it works best for you.

“If you're in doubt about whether or not you're ready to begin marathon training, just start the training plan. If you can get through week one without feeling completely exhausted, keep going!”

Month One: Weeks 1 Through 4

asian femme stretching in the sun

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Watson says that the first month of a marathon training schedule is all about building that solid running base, getting the runner used to running several runs per week, and doing all that while avoiding injury. “It provides the foundation for the rest of the plan, so we can begin to layer on more miles in the later months.”

  •  Running Schedule: Four Days a Week

Watson recommends three regular runs throughout the week, starting at the three- to five-mile mark. “These are to build up that base mileage, get the runner on their feet, and improve their running economy.”

The fourth run of the week is your weekly long run, which normally starts between six and nine miles, but progressively builds in distance each week, he says. 

  •  Strength/Cross Training: One Day a Week

Strength training, including yoga, weight training, or bodyweight and flexibility work, is a core part of all his training plans. “Strength training can address the weaknesses and imbalances caused by so much running," Watson explains. "Running is unidirectional, so it's expected that it leaves some muscles tight and others weakened. A good strength training regime, focusing specifically on hips and upper legs, can counterbalance the effects of running and reduce the risk of injury hugely.”

He says strength training also makes you stronger, faster and improves your endurance. 

“Some runners also implement a speedwork session, like interval training, into their marathon training plan,” he says. “I typically only advise these for experienced runners because it adds a layer of intensity to an already busy training plan.”

Watson says to make sure you address any potential injury right away, so it doesn’t turn into a larger problem. Talk to a doctor, trainer, or physical therapist to get it taken care of.

"Don't be too strict about doing every run in the training plan," says Watson. "Sometimes life gets in the way, and we end up burned out, and it's better for your overall training to miss one day training. That said, try not to miss the long runs. If you're going to skip a day, skip one of the regular training runs."

Month Two: Weeks 5 Through 8

Your running and training schedule remains the same, with four days running, one day strength training, and two days resting, but you will start adding in more mileage.

  • Running Schedule: Four days a Week

You will continue with three days of shorter training ones, with one weekly long run. “By month two, your [three] training runs should get just a little bit longer and should be in the five- to seven-mile mark,” says Watson.

Your weekly long run should be progressed to 13-16 miles.  

“Your long runs will be getting progressively longer and more taxing. Remember to keep the pace slow and relaxed on these,” he says. “Once you're consistently doing long runs of more than one hour, you should bring along water and some fuel—such as energy gels—to keep your hydration and energy levels topped up.”

  • Strength/Cross Training: One Day a Week

Buckingham suggests adding in low-impact exercises, such as swimming, biking, or the elliptical, on your cross-training days. “The reason running causes so much muscle damage is that it’s weight-bearing. This means the body must work against the full force of gravity with each step. Cross-training should aim to minimize the pounding on the muscles and joints by reducing or removing this pounding."

He also suggests strengthening exercises like squats, deadlifts, lunges, and plyometrics.

Watson says at this point in the plan, you should include “step-back weeks,” in which you don’t increase the mileage you run. “These weeks allow your body to consolidate the gains it's made in the prior few weeks.”

Month Three: Weeks 9 Through 12

androgynous black person drinking water

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“Month three is when your training mileage gets intense and eventually peaks,” says Watson. “This is the phase where injuries and exhaustion are most prevalent, so you mustn't ignore any early indicators of injury and ensure you're resting well.”

  •  Running Schedule: Four days a Week

Your running schedule should consist of three days, with training runs composed of six to 10 miles. Your long run slowly tapers up in mileage and should be between 14 and 19 miles for the first three weeks—and then it is time for the one big run.

“In month three, your overall mileage should gradually increase every week, and peak at the end of the month with your longest training run, which should be 20-22 miles,” says Watson.

“You want to do the longest long run of 20-22 miles only once and do it around three to four weeks before the marathon. Then enter the taper, which is a gradual reduction in training mileage,” says Watson.

If you feel tired, don’t be afraid to skip a run here and there to help your body recover, but it is important to complete the long run one time in this stage of your training. “If you can complete 20-22 miles in training, you'll be able to get through the 26.2 miles on race day —especially after tapering, and with your race day head-on!” he says.

  •  Strength/Cross Training: One Day a Week

Continue doing one day a week of strength training or low impact cross training. Activities like yoga or Pilates are great to help improve your flexibility and mobility. 

Month Four: Weeks 13 Through 15

“On month four, you're now into your taper, so your mileage should decrease by about 25-30 percent each week,” says Watson. “The taper is all about allowing your body to recover from the rigors of high-mileage marathon training, so when it comes to race day, your muscles are recuperated, you're fueled up, and you're ready to go.”

  •  Running Schedule: Four Days a Week

For your shorter training runs, aim for seven miles the first week, four miles the next week, and then three miles. Your longer runs on that one day a week should be between 12 and 8 miles.

“A good marathon taper involves a week-by-week decrease in the volume of training (or mileage) while maintaining the same level of training intensity. So don't slow down during your taper; just go for gradually shorter runs,” he says.

  •  The Week Before:

“In the week before a marathon, I recommend going for a short (three- to five-mile) easy run every other day,” says Watson. “By this point, there's nothing you can do in your training to improve your running ability. Instead, these runs are about limbering up your legs and having your body primed to run hard on marathon day. So keep the intensity levels low and comfortable."

He says at this point it is a good idea to do some low-intensity cross-training activities, like swimming or yoga, but don't try anything new this week!  

Make sure you get plenty of sleep the two nights before your marathon and take a full rest day the day before your marathon. Be proud of all your hard work and perseverance and go into the marathon confident in your body and your abilities. You are ready!

Post-Marathon Care

group of friends resting after run


Before you do anything else, give yourself a huge pat on the back. You accomplished something that not many people have.

“Following the race, you will likely be dehydrated,” says Buckingham. “A key to rehydrating is to consume a sodium-containing drink. The sodium in your drink will help your body retain water and rehydrate more quickly.”

These sodium-containing drinks, such as sports drinks like Gatorade, help you rehydrate faster than water alone. Buckingham says it is also important to eat a nutritious meal after the marathon, including high-quality protein to help your muscles repair.

“Whether it’s your first or your 40th marathon, chances are your legs are going to be sore," says Watson. "A great way to help speed up your recovery is to perform non-weight bearing exercise in the days following the race."

He recommends exercises like swimming and cycling. These exercises are beneficial is they increase blood flow to the legs without the excessive pounding that running produces. "More blood flow to the legs means that more muscle repair can occur," Buckingham says.

He says to avoid a massage for a few days after the marathon. “A massage will cause more muscle damage and could further delay your recovery. A caveat is if it is a very gentle massage. This can help increase blood flow without causing additional muscle damage,” he explains.

Lastly, take some time off of running and let your muscles and joints fully recover. “Running a marathon and the 12-20 weeks of training that accompanies it can be physically and mentally taxing. Allow yourself time to reset to avoid burnout and overtraining.”

Article Sources
Byrdie takes every opportunity to use high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial guidelines to learn more about how we keep our content accurate, reliable and trustworthy.
  1. Bhuva A, D’Silva A, Torlasco C, et al. Training for a First-Time Marathon Reverses Age-Related Aortic Stiffening. J Am Coll Cardiol. 2020 Jan;75 (1):60–71. doi:10.1016/j.jacc.2019.10.045.

  2. Mayo Clinic. Mayo Clinic Q and A: Running for Better Health. Published October 25, 2020.

  3. The American College of Sports Medicine. Selecting Running Shoes.

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