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Couch to 50k Training Plan (8, 12 and 20 Weeks Out)

Couch to 50k Training Plan (8, 12 and 20 Weeks Out)

First of all, I have to say that I’m happy you’re here. Even if you’re just dipping your toes in the water out of curiosity or simply trying to wrap your head around what it would take to run an ultra marathon, you’ve taken the most important step—the first one. You’ve begun!

Or maybe you’ve run a couple ultras already but they were a long time ago or they were absolute suffer fests and you want things to go a bit more smoothly for your next. Well done on seeking out a resource to help you in your journey.

No matter your origin point, I’m here to take the guessing work out of the ultra-marathon equation and provide you with all the information you’ll need to go from your current fitness level (whatever that may be) to finishing a 50k.

I’ll provide you with a full 12-week training plan as well as instructions on how to adapt the 12-week plan into 8 and 20 week plans depending on your needs.

If you’re starting from scratch, I’d recommend opting for the longer 20 week plan.

If you’re already fairly fit from running or some other endurance sport, the 12-week plan might be just the perfect fit for you. And lastly, if you’re in a crunch and only have eight weeks until your race, or if you simply can’t imagine committing any more of your time than that, I’ve got a plan for you too.

I’ve been running ultra marathons since 2011 and have over 40 ultra finishes from 50k to 100 miles. I’ll never ever forget my first ultra, the Flagline 50k in the mountains outside of Bend, Oregon.

I made all the rookie mistakes you can imagine: I ran the early miles way too hard, I didn’t consume enough calories or electrolytes, I didn’t adequately prepare for the terrain I would face on race day, and generally speaking, I let a sour attitude take-over at the finish line because I thought I deserved to do better.

Had I known then what I know now. But wait, this isn’t about me. I’m here for you! I’m here to help you avoid the mistakes I made and guide you to a successful and fulfilling 50k experience. So let’s get into it!

Is a “couch to 50K” actually possible?

One hundred percent YES! I absolutely believe that you can finish a 50k with no baseline fitness to speak of. That said, there’s always the possibility that things could go wrong during training and derail your race plans, but really, that could happen to anyone.

I would say, however, that if you are opting for the eight week program, you are running a higher risk of injury by compressing your training and leaving yourself less wiggle room to adjust your timeline in response to your body’s needs and overall fatigue.

With running, the worst thing that can happen is that you develop an injury that prevents you from completing your goal. I’ve had to pull out from my fair share of races and sometimes you can do everything right and still get a injury. What we’ll aim to do is structure the training plan to give you your best shot at success.

One thing you have going for you is that, in my opinion, a couch to trail 50k is actually in some ways easier on your body than a couch to road marathon program. At this point you probably know that 50k is roughly 31 miles—about five miles longer than a marathon.

The key difference, however, is that the vast majority of 50k races take place on trails. And from an injury perspective, trails are your friend. Why? Because they’re soft and your body suffers far less pounding and trauma than it does on the roads.

On trails, you’ll be adjusting your speed to the terrain, hiking a lot of the uphills, you’ll be stepping over fallen trees and rock-hopping over creek beds, all of which trigger and stress different muscles in your lower body. It’s the repetitive metronomic nature of road running that leads to the majority of injuries.

Training for a 50k in 12 weeks – Here’s the plan…

Speed Work/Intervals

In the plan above, you’ll see speed work on Wednesdays starting at week 5. Here’s further details on how you can structure these…

  • Week 5: 1 mile warm up, 3 by 3 min hard with equal recovery, 1 mile cool down
  • Week 6: 1 mile warm up, 5 by 2 min hard with equal recovery, 1 mile cool down
  • Week 7: 1 mile warm up, 4 by 3 min hard with equal recovery, 1 mile cool down
  • Week 9: 1 mile warm up, 6 by 3 min hard with equal recovery, 1 mile cool down
  • Week 10: 1 mile warm up, 6 by 2 min hard with equal recovery, 1 mile cool down
  • Week 11: 1 mile warm up, 3 by 3 min hard with equal recovery, 1 mile cool down

If I prescribe “4 by 3 minutes hard with equal recovery,” this means you are to run four sets of 3 minutes hard running followed by 3 minutes of stationary recovery or slow jogging. During the three minutes of hard running, you don’t want to be going at 100% effort; you should be uncomfortable and breathing hard, but closer to an 8 or 9 out of 10 on the perceived effort scale.

Keep in mind that you’re going to get fatigued throughout the workout so don’t go too hard on the first couple intervals. Do whatever it takes to get excited about working hard on these days; you’ll get out of them what you put it so make them count!

The long run and easy runs…

Fundamentally, the goal is to slowly build your volume (amount of running per week) over time so that you build fitness and prepare your body to cope with 31 miles of running, but not build volume so quickly that you get injured. Our bodies get stronger through phases of stress and recovery.

You break down your muscles and place stress on your cardiovascular system so that afterwards, with proper fueling and recovery, they rebuild and strengthen so that they can handle more work then they previously could.

I will be prescribing 3-5 days of running per week with one long run day and one interval workout day per week. Your other days will be shorter easy runs where you’ll be developing efficiency and actively recovering from your long run or intervals.

The “long run” is pretty self-explanatory; it’s one run per week where you push your endurance system and train your body to go for a long time. We start out conservatively and bump up the long run mileage a few miles per week.

Easy days are just as they sound. Pick a trail, run from home, grab a friend to join you, whatever works; the goal is to just get the run in and not worry about pace or effort. Your body is absorbing your training during these runs and doesn’t need any more stress than you’ve already placed on it. Go EASY.

My only other advice would be to make sure some of your runs are on terrain that is similar to what you’ll find on race day. If there will be lots of shorty steep climbs on the 50k course, make sure to integrate those types of climbs into your training. You shouldn’t be tackling anything on race day that you haven’t already done in training, except for actually covering the full 31 miles.

8-week 50K training plan:

To turn this 12-week plan into an 8-week plan, simply remove weeks 1, 3, 5, and 10. Disclaimer: eight weeks is not a lot of time! If you already have some baseline fitness, then you should be fine, but if you’re truly starting from scratch, I’d recommend cutting yourself some slack by doing the 12 or 20-week program.

20-week 50K training plan:

To turn the 12-week plan into a 20-week plan, I’d recommend using the 12-week plan as written but instead of racing the 50k at the end of week 12, find a shorter race in your area to do as a tune-up for your 50k. Look for a race distance in the 10k-30k range.

Then, after the tune-up race, repeat weeks 5-12 but tack on two extra miles to each Saturday long run. You will be surprised how much you will have improved the second time through!

Cross-Training For Ultra Runners

In the training plan below, I ask you to complete one day per week of cross training. Shoot for 30-60 minutes. What is cross-training? Well, I want you to view it as anything that gets the blood pumping and that you enjoy doing. Don’t do anything that’s emotionally taxing or stressful.

This should be an activity that allows you to move but still recharges the battery. Some examples: yoga class, rock climbing, neighborhood bike cruise, chopping wood, dancing all-out to Michael Jackson’s Thriller on repeat, swimming across a lake, or shadow boxing against your boss.

If you can hold a beer and not spill while doing it, I’m going to say it doesn’t count as cross-training. So no horse shoes, bocce ball, or floating the river.

This is your opportunity to flush out the legs, burn a few calories, use some muscles that you don’t use while running, and help build your supportive body structure so that you can continue to run healthy.

Injury Prevention, Rest, and Recovery

One of the primary requirements of a successful and enduring foray into ultra running is that you always need to be listening to your body. Don’t get too caught up in mileage and numbers or subjective metrics for what may or may not get you to the finish line. The ultimate goal of any long distance training program is not actually to get you to the finish line, the real goal is to get you to the starting line!

The race itself will be hard and you can challenge yourself and push as hard as you can on that day, but if you’re not healthy, you won’t even be at the race. If following this principle means you don’t hit your weekly targets, that’s okay! Do what you can, don’t be too stubborn; make sure you listen to your body and make it to the starting line to give yourself a fighting chance.

Beyond listening to your body and adjusting your training to prevent injuries, you’ll also want to set yourself up for success with good recovery habits. First off, sleep is HUGE. Get as much of it as you can. I’m a seven hour a night guy. I can handle less in fits and spurts, but over time I need to average about seven.

I recommend shooting for more than that. Ten if you can! Eight to nine is great. Seven, maybe six, is the bare minimum. Anything less than that and I really don’t think you are going to be able to absorb your training and sufficiently recover.

Related Articles:

What is a Recovery Run? (Benefits and FAQs)

How to Taper for a 50k Trail Race

Lastly, nutrition. You are what you eat, right? What are you putting into that precious body of yours? A few quick tips without getting too deep in the diet morass. First, make sure you’re getting some protein into your body within 30-45 minutes of finishing your runs. Second, moderation is key for ultra runners.

Listen, running a lot of miles is hard and sometimes you are going to splurge here and there on meals; that’s totally fine. But if you’re putting away a quart of rocky road every night of the week, well, that’s just not good for you and you aren’t going to see the fitness gains that you would if you adopted a more balanced approach.

Maybe shoot for one quart of ice cream a week and on the other nights eat fruits and berries or even frozen yogurt.

Personally, I like the 80/20 rule. Try to “be good” 80% of the time but don’t beat yourself up when you’re “bad” 20% of the time. Never restrict calories, you need to fuel, but you are in control of what types of calories you put into your body. Use common sense here and you’ll be fine.

What is a good time for a first 50k?

This is a question I get a lot, but it’s so subjective that it’s almost unanswerable. What I’ll say is that ANY time is a good time for your first 50k! What’s unique about ultra marathons is that there are usually cut-off times that you have to meet at each aid stations along the course, which are usually about every five miles or so.

The race organization will provide the times at which you’ll need to reach each aid station in order for them to allow you to go on. But don’t let that scare you! Usually they’re very lenient for a 50k. They really want to see you finish the race so that you have a great experience and tell all your friends about their incredible race!

But if they didn’t enact cut-off times they could be out there forever waiting for runners to come in, maybe even well into the night, and that’s not fair to the volunteers and employees manning the aid stations that need to get home to their families. Also, sometimes State Parks or the U.S. Forest Service places hard-stop time limits or guidelines on the race that force the race organization’s hand.

So a finish means you beat the cut-off times and that’s something to celebrate.

Also, ultra marathon times are very course dependent. I had a great race on a mountainous 50k course in Montana that took me six hours, but I’ve had a mediocre day on a flat fast 50k course where I finished in four hours. With that in mind, I’d try to steer clear of using time as a performance metric in a 50k.

Instead, effort-level and keeping a positive attitude are likely better ways to gauge success. Did you feel like you gave it all you had on the day? Did you manage your emotional low points without mentally beating yourself up?

If you absolutely must have a time goal to motivate you, I get it. What I’d recommend is going to the race website for your 50k and scroll back through the results. What’s your goal? Do you want to shoot for top 25% of the field? Top 50%? Top 75%? Not be last? You can get a really good idea of what time it’ll take on that particular course to achieve each of those goals.

How should I pace myself for a 50k?

Pacing is absolutely key to a successful completion of a 50k and is one of the most common missteps for first time ultra runners. Why? Because it’s an acquired skill. So then how do you learn to pace yourself in a race? By learning to pace yourself in training! Everyone has a sweet spot where the internal engine is working hard but not going over that red line.

A great way to gauge if you’re working too hard is whether or not you can maintain a conversation while running. During your interval workouts, you shouldn’t be able to have a conversation with a running partner because that would mean you aren’t quite working hard enough.

But during a 50k race, you really want to stay at that nice and easy pace where you can chat with other participants in the race. Because eventually, even that nice easy pace is going to feel really hard!

Apart from simply getting a feel for your effort and responding to your breath, if you enjoy technology and analytics, a heart rate monitor is a useful tool to make sure you’re staying in the appropriate effort zone.

If you know that your body starts to crash when you exceed 140 beats per minute, then you can monitor your heart rate monitor to make sure you don’t step over that threshold. The tough part is knowing what your personal threshold number is. Read more on heart rate training here.

You can also create multiple effort zones and get very technical about it all, but that’s a rabbit hole that in my opinion should mostly be reserved for more experienced runners who really want to optimize performance. At this point, I think it’s best to learn how to listen and respond to the natural messages your body is sending you and develop your own intuition.

How many miles should I be able to run a week?

If your goal is to finish the race, I think your biggest week of running should at least mimic what you’ll see on race day. If you are racing a 50k with 5,000 feet of elevation gain during the course of the race, then that’s a good distance and elevation gain to shoot for during your biggest weeks of training.

I apply the same rule to 100 mile races. Before running UTMB, a 100 mile race in the Alps, I made sure to get at least one 100 mile week with 30,000 feet of vertical gain. I did this to build both the required physical strength but also mental confidence.

What should I eat during a 50K race?

In short, whatever you can. Your average ultra runner consumes 150-300 calories per hour and the majority of them do so by consuming what we endearingly call “gels”. Generally speaking, gels are a gooey substance made up of carbohydrates (sugar), electrolytes (sodium and magnesium), flavor additives, and amino acids.

They come in little convenient packages that you tear the top off of and squeeze into your mouth with each serving usually consisting of 100 calories a piece.

If gels don’t sit well with you—don’t stress—how about some gummies, blocks, chomps, waffles, powder drinks or bars? This plethora of options didn’t used to be the norm, but the nutrition for endurance athlete niche has gone gangbusters so there’s something for everyone.

Related article: Couch to 5K Training Plan (Free PDF Printable)

What I’d recommend is that you head into your local running store and try out whatever looks tasty! Then, during your training, start testing out various options until you land on the food source that works best for your stomach and sensibilities.

In a 50k, you can plan to use your own food during the race or you can eat what the race organization provides at the aid stations. If you have an iron gut and stomach sensitivity is not an issue, heck, save yourself the hassle and just plan to eat whatever gels or foods that happen to be at the aid stations.

But if you lean more towards the queasy side or if you absolutely need your boysenberry-lime-mango gel flavor and those are the only things you can get down, then by all means, stock up on those and use them in training so that you’re prepared and ready to go on race day.

You Can Do This!

Are you pumped? Nervous? Scared? I’d say those are all very common and normal responses to what you are about to embark on. Running your first 50k is a huge deal! I believe the steps you are taking now are going to pay huge dividends; more than a slimming waistline or another tic off the bucket list.

What I hope for you is that you fall hook, line and sinker for this new ultra running lifestyle and start to experience the love of a uniquely strong community. If something happens and you aren’t able to complete your 50k goal, that’s okay, don’t stop running! Re-calibrate, adjust your race goal target, and keep at it.

Reach out for help when you need it, lean on your friends and other runners you meet along the way to keep the internal fire burning.

The trail and ultra running community has given me so much more than fitness. I’ve developed relationships that will last a lifetime and a daily practice of getting out the door to run, clear my head, and soak in a constant stream of positive energy.

I really hope you get to experience the same thing! I’d love to know if you benefited from this article or if you end up using my training plan so please feel free to reach out to me directly.

“A journey of a thousand miles begins with a single step.” -Lao Tzu.

You got this!

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  1. Al Shaffer says:

    Chase, I think your training plan looks great, and I wish I’d had it a few years ago when I ran my first 50k (followed closely by a 50M). I’m running a 35k in 12 weeks, and wanted to ask if you have advice on how to modify your 50k plan accordingly. Thanks!

  2. Meloni says:

    Hi! I’ve got a 20k in 8 weeks!!!!! My last 1/2 marathon was about 7 years ago and I haven’t done anything since. I’ve run about 5-6 1/2 marathon road races. This will be my 1st trail race. Any suggestions on training mileage for a 20k rather than a 50??? I LOVE your article and would love to train with your schedule/ plan

  3. Michael Heitholt says:

    That’s great, thanks! Perfect timing as tomorrow is scheduled for my first one. Much appreciated!

  4. Sorry about the confusion there. I checked with Chase and he recommends 1 to 2 miles for both warm and cool down, plus the speed portion. This is not two different workouts. Hope that helps!

  5. Michael says:

    Are the Wednesday prescribing 3-4 miles in addition to the speedwork? Or is that the estimation if you do the 1 mile warm up, cool down, and prescribed speedwork totally 3-4 miles?