How To Run 100 Miles: Our Expert Guide + Training Plan

There’s nothing quite like the thrill of crossing the finish line of a 100-mile race. The adrenaline, the exhaustion, the emotional whirlwind—it’s overwhelming in the best way.

I had tears of joy streaming down my face after finishing my first 100-miler… and my second… and yep, even my third. Every. Single. Time. That feeling never gets old. You feel unstoppable… and completely wrecked all at the same time.

In this guide, I’m sharing my top ten tips—straight from the coach’s playbook and personal experience as a multi-time 100-mile finisher—to help you train smart and get to that finish line feeling strong.

You’ll also find our free, downloadable 100-mile training plans to help you map out your journey, your way.

#1: Be Prepared to Put in the Time

Before you hit “register” on your first 100-mile race, make sure you’re ready to commit the time it takes to train properly.

The last thing you want is for your training to feel like a burden or another stressor on your already-packed schedule. Ultra-distance running isn’t just a weekend hobby; it’s a lifestyle, and it demands a lot of your time and energy.

So, how much time are we talking?

A lot. Expect to run 5–6 days a week, with two of those days often dedicated to back-to-back long runs—one of the key pillars of 100-mile training.

You’ll also want to include two strength training sessions each week to build durability and prevent injury. That said, the exact structure will depend on your personal goals, experience, and the plan you’re following.

But running is just the start.

You’ll also need time for warm-ups and cooldowns, proper rest days, 8–9 hours of sleep each night, stretching or mobility work, foam rolling (or the occasional sports massage), and fueling with a nutrient-dense diet that supports your mileage.

Toss in some self-care to keep your mental game strong, and yeah, it’s a lot. But if you’re excited, motivated, and ready to go all in, it’s absolutely worth it.

#2: Choose Your Training Plan

No matter what your goal is, whether it be running your first 100-miler, trying to improve on a previous time, or competing, you will need a detailed training plan to ensure success. 

The total running time commitment will vary depending on your specific goal.

However, our 100-mile training plans are all 6 months in length, no matter what your level, assuming you already have a solid running base. If not, the total length of the training plan would need to be extended.

Let’s get an idea of our running time commitment for each type of goal.

• First 100 miler: 5 days a week 
• Improver 100 miler: 5 days a week 
• Competition: 6 days a week 

As for time commitment, this is just the tip of the iceberg.

What kind of training does a 100-mile plan include?

Mileage, and lots of it

Whether you are running your first or are a 100-mile veteran, time on your feet is imperative.

This is why you need to ensure you have enough free time in your schedule to train properly. On race day, most of us will be out there for the entirety of a day, most likely more, so you’ve got to put in the time and get your body used to tolerating a lot of time on your feet.

Mileage will depend on your specific goal, so look at our different 100-mile training plans to better understand how much weekly mileage you will need to put in.

Effort

Most of your weekly mileage will be at a comfortable, conversation pace, also known as long, slow distance, or “LSD” runs.

80-90% of your training runs will be at this pace. So get ready to rally some friends to keep you company, or put together some playlists or audiobooks to keep you entertained.

You may work in one speed session a week to improve your running economy and your base running speed, but for the most part, prepare yourself for long hours of trotting about.

Cross Training

When training for any event, focus most of your time on practicing the sport you’ll be competing in, in our case, running. However, if you are unable to run the number of days in your plan, or are prone to injury, you can add in some cross-training such as biking, elliptical, swimming, or rowing. 

I suggest limiting these sessions and trying to get outside on the trails and pavement as much as possible. However, cross-training does come in handy as an alternative if you are battling any sort of injury during your training period, or weather conditions don’t permit you to train outdoors.

Related: The Bear 100: 13 Lessons Learned From A 100-mile Ultra

Long Runs

This is where you will spend the majority of your training time, so clear out those weekends for the next six months. You are going to be busy.

As mentioned, these runs should be done at a very easy pace. When you finish each long run, you shouldn’t feel depleted or overtired but as though you could have continued running. 

Also, remember that every long run should be used as a race simulation.

Practice everything you plan to do on race day during these runs, such as how you will hydrate with fluids and electrolytes, fuel with gels, other sports supplements, or “real” food choices, avoid blisters with the right socks, and so on.

Train in similar weather and terrain that you will find at your race, practice your race strategies, and even wear the same clothing and gear you plan on using the day of.

Every aspect should be taken into consideration and well-rehearsed so that you can be as prepared and comfortable as possible.

Related: Why I’m Running 100 Miles

Back to Backs

Speaking of long runs, and when I mean runs, plural, I’m not just referring to all of the long runs throughout the training process. I also mean there is more than one long run per week.

There are two per week, usually scheduled on Saturdays and Sundays (your availability will determine the schedule). 

These are the famous “back-to-backs” everyone talks about. They are a surefire way of getting used to running on tired legs and really come in handy for the second half of the race.

Contrary to popular belief, your long runs shouldn’t be extra-long and burn you out or cause you to fail to recover properly. Instead of piling on close to your total mileage in one or two days, you’ll split them up throughout your week, taking extra advantage of the weekends, so you can still rack up the miles but in a much safer way. 

Don’t worry; you will be prepared if you follow your plan to a T.

It may seem like low mileage, but you’d be surprised what the body achieves on race day. There is always doubt going into your first 100-miler because you think there is no way you could possibly run double or even more than your peak week-long runs, but you will get to that finish line, I promise.

#3: Plan Your Peak Week

This should be scheduled in your training plan 3-4 weeks before your race. You’ll want to peak and then have plenty of time to taper off before the race to be sure you are rested.

You won’t lose precious endurance or fitness during your taper; instead, you’ll be able to rest up and arrive at the starting line strong and recovered. 

My favorite way to peak for a 100-mile race is choosing a race about four weeks out. 

If there happens to be a race that works with your peak week mileage four weeks before your 100 miler, sign up for it.

You can enjoy your long run with lots of other runners and have assistance along the way. It will be much easier logistically than organizing such a long run on your own. 

It is important, however, not to get competitive out there. You don’t want to risk a burnout after all the work you have put in.

#4: Study The Course

Before race day arrives, there are some logistics you’ll want to understand to help you feel prepared and confident at the start line.

For example, 100-mile races allow drop bags—these are small bags you pack ahead of time with items like extra food, clothing, headlamps, or spare shoes. They’re delivered by the race crew to specific aid stations on the course so you can access your gear during the race without needing a crew.

Find out where your drop bag will be located on the course so you can plan accordingly.

Aid stations are spaced throughout the course (often every 5–10 miles) and stocked with water, electrolyte drinks, snacks, and sometimes hot food (especially at night). Know what will be available. You’ll also want to know if the aid stations allow crew access.

If you have a support crew, find out where they’re allowed to meet you. These designated points (usually larger aid stations) are where your crew can help you with gear changes, food, emotional support, and motivation. Outside of these points, they typically aren’t allowed to assist you.

Some races (especially mountainous or remote ones) require runners to carry specific gear like a headlamp, emergency blanket, jacket, phone, or GPS tracker. Check the gear list and make sure you’re ready to carry everything required at check-in or on course.

Unless you’re elite, you’ll be running through the night. Most runners bring a primary headlamp and a backup light or batteries.

Understand how the course is marked ( flags, reflective tape, signs) and whether navigation tools (map, GPX file) are recommended. Some races are well-marked; others may require self-navigation.

Think about transportation if the race ends at a different point than the start. Have clean clothes, food, recovery gear, and support ready for when you finish. Some races also offer showers, meals, or shuttle buses.

Some races also allow pacers, who are friends or volunteers who can run with you for a section of the race (usually after the halfway point). They’re there for safety, motivation, and moral support, but they can’t carry your gear or physically assist you.

You’ll also need to be aware of cut-off times, which are strict time limits at certain checkpoints or for the race as a whole. If you don’t reach these points by the designated time, you may be pulled from the race for safety reasons, even if you feel well enough to continue.

Knowing these terms and how they apply to your specific race will help you make smarter decisions on race day and avoid any surprises when you’re deep into the miles.

#5: Run At Night

Unless you are a speed demon and have run plenty of 100-miler races before, you are going to run in the dark at some point during your race. Do not leave this until the day of the race to figure it out.

You want to work night runs into your training plan so that you can get used to running in the dark. It’s not as easy a feat to dodge obstacles and jump over roots in the pitch black of night as on a bright sunny day. 

Fire up that headlamp and get out of the trails. You will also want to learn how your headlamp works, how to adjust the stream of light to illuminate the trail ahead properly, and even how to change the batteries in the dark.

You will be happy you practiced this beforehand, so it doesn’t feel as intimidating the night of. 

The dark won’t be the only obstacle for night running, but running overtired and on zero sleep. Try a really late run so that you can feel what it will be like to run physically and mentally tired while tackling trail obstacles all at the same time. This will be a valuable experience on the day of the race.

#6: Hit The Gym

Another key aspect of your training that I cannot stress enough as a running coach is the importance of strength training.

I encourage all my athletes—regardless of distance—to incorporate strength work into their weekly routine because I’ve seen firsthand how transformative it can be.

Personally, strength training has made me a more durable, efficient, and injury-resistant runner. And when it comes to ultra distances, especially the 100-miler, that extra strength can make all the difference.

Your legs will inevitably feel like giving out at some point, but if you’ve built a strong foundation, they’ll keep going when the fatigue hits hardest.

At the gym, prioritize training your legs, back, and core—the muscle groups that carry the most load when you’re running for 24+ hours with a gear-filled vest, hiking poles, headlamps, hydration, and layers on your back.

I recommend doing two full-body strength sessions per week, each lasting about 45 minutes, focusing on compound movements such as squats, lunges, deadlifts, step-ups, push-ups, and rows. These exercises engage multiple muscle groups simultaneously, improve coordination, and simulate the demands of running on variable terrain.

Build that strength now, and trust me, you’ll be grateful for every rep when you’re still moving forward at mile 80.

Read our complete Weightlifting Guide For Runners

#7: Train Your Brain

To run a 100-mile race, you need to be mentally prepared. They say 50% of 100-milers are mental, and guess what? 

They aren’t kidding. 

You need to be able to fight against your brain telling you to stop over and over again. Don’t give in to the negative thoughts about why you decided to do this in the first place; forge ahead. We can not let our minds beat us and force us into an unnecessary DNF. 

So, during your long runs, test these tips out.

Mantras

Use mantras to help keep you going during long runs and on race day. Think positive thoughts and smile; it will help you through those challenging moments. 

Here are a few to get you started:

• “This too shall pass.”
• “Strong, confident, relaxed”
• “I can do this.”

Count Steps

I count my steps in bouts of thirty or sometimes one hundred. I simply count each step until I reach that designated number and then start again. It really helps occupy my mind and keep me focused on something other than the negative thoughts. 

Distract yourself with what’s around you and enjoy gorgeous Mother Nature. You can also propose mini-goals during training, such as reaching specific landmarks, and play around with Fartlek runs, which is “speed play,” at your discretion.

#8: Focus on Self-Care

You are going to be beating your body up quite a bit during these months, so you need to pamper it as you go, so nothing breaks along the way.

Stretching

Yes, we all dread it, but we need to dedicate these few precious minutes after workouts and long runs to stretch out our muscles. This will help you recover for the next day of trail running and prevent injuries.

Focus on stretching your legs, hamstrings, quads, calves, and glutes.

Massage

It’s very comical when non-runners hear you are going for your “massage” again and tease you for indulging yourself. Little do they know…it hurts!

Ideally, a massage every other week would keep you in tip-top shape. Try scheduling massages for the afternoon or evening before your rest day. They can leave you as beat up as if you had done a speed workout.

Physical Therapy

If something begins to bother you during your training, don’t wait until it’s too late to see a physical therapist. It’s most likely muscle tightness, and a sports massage will alleviate the problem. However, you want to be sure there’s nothing else that will hinder your training. 

Don’t wait, make an appointment just as you begin to feel any pain that is out of the ordinary.

Footcare

Runners, in general, need to take good care of their feet, but it may come as no surprise that ultrarunners need to do so even more.

Your feet will be well-trained by the wear and tear of the miles and miles you will be putting in, so take care of them. Get a pedicure or give yourself one regularly.

Hydrate your feet with lotion, keep your nails short, and file down calluses so they don’t get too deep.

#9: Train Your Race Strategy

Know your race details. I can’t stress enough how important it is to know what you are getting yourself into to be as well-prepared as possible for race day.

Hydration

Be familiar with the weather you will encounter on race day and plan your hydration accordingly. Take a sweat test to determine how much liquid you lose per hour, and try to consume 80% of that amount during your long runs. 

Also, choose specific hydration products that will work for you and practice using them consistently. You want to be sure they sit well in your stomach and won’t give you a problem on the big day.

Nutrition

Just as you need to practice your hydration, you need to practice your nutrition routine.

Trial and error with food and sports supplements is the only way to determine what works. Calculate how much and how often you need to consume calories and carbohydrates according to your weight. You can use this equation to get a general idea of what you need:

Weight in kilos = carbs per hour

Pre-run

Before each long run, try different pre-run fueling to see what works best for you. Is it a banana? Toast and honey? Oatmeal? Try a bunch of options, and track how you feel on each run.

During

This strategy is one of the most challenging to figure out. First, try out various energy products and incorporate solid, “real” food. You’ll likely be running for most of the day, if not the entire day, depending on the race, so you’ll get really hungry. 

Try peanut butter and jelly sandwiches, cookies, chips, nuts, or anything you think would work for you. The race will let you know what they will have at the aid stations, so you can give some of those foods a try and see how you feel. 

Training your body to eat solid foods while running is not easy. Forcing down calories when you no longer want to is a challenge in itself, and it must be trained.

Post-Run

Part of your training also includes your post-long run and workout recovery. Find a recovery drink or protein that works for you, and try to consume it within 30 minutes of ending your workout. 

General Nutrition

You’ll be running more than ever during these six months, so fueling your body on and off the track is crucial.

Train yourself to eat healthy, substantial meals and snacks consistently. If you need someone to get you on track, see a sports nutritionist. Tell them about your crazy goal, and they can create a helpful plan.

#10: Organize Your Schedule

It’s very important to schedule each piece of your training into your calendar to make sure you don’t forget any tiny detail. 

Here’s a checklist, so grab your calendar, and let’s get planning!

• Runs
• Stretching 
• Weight training
• Meals and snacks
• Nutritionist appointments
• Massages 
• Physical Therapy
• Foot care
• Sleep

By slotting out the time you need for each piece of your training, you will alleviate a lot of stress. Plan each month in advance and check your calendar each evening to know what you need to get ready for the following day. 

I know this is an overwhelming amount of information, but running a 100-miler is an overwhelming goal, and you need to be as prepared as possible to be successful. 

The most important thing is that you enjoy the process. This is an amazing challenge you have set for yourself, and you should already be proud for even considering this. Now, let’s make that dream a reality, and let’s get training! 

100 MILE ULTRAMARATHON TRAINING PLANS