Training Plan for 50K
A 16-week plan to take you from marathon runner to ultramarathoner. Full week-by-week schedule with back-to-back long runs, nutrition strategy, gear list, mental preparation, and race day tactics for your first 50K.
What Is a 50K and Who Is This Plan For?
A 50K is 31.07 miles, making it the entry-level ultramarathon distance. It is only 4.9 miles longer than a marathon (26.2 miles), but the experience is fundamentally different. Most 50K races take place on trails with significant elevation gain, aid stations every 3 to 5 miles, and generous cutoff times of 7 to 10 hours. Walking is not just accepted; it is expected.
This training plan is designed for runners who have completed at least one marathon and are currently running 30 to 40 miles per week. If you have not yet run a marathon, do that first. The marathon teaches you about fueling, pacing, and mental toughness over long distances. All of those skills are prerequisites for ultra running.
Ultra running is a different sport than road running. It is slower, more communal, and more focused on the experience than the clock. The person finishing in 10 hours gets the same finisher is medal as the person finishing in 4 hours. The ultra community celebrates everyone who crosses the finish line.
Distance
31.07 miles (50 km)
Plan Duration
16 weeks
Peak Mileage
55 to 57 miles/week
How 50K Training Differs from Marathon Training
More time on feet, less speed work
Marathon training emphasizes tempo runs and race-pace sessions. Ultra training prioritizes total time on your feet. Your long runs are slower but much longer. Speed work is reduced to one session per week, mostly hill repeats that build functional strength for trail racing.
Nutrition is everything
In a marathon, you might take 2 to 3 gels. In a 50K, you need to consume 200 to 300 calories per hour for 5 to 8 hours. That is 1,000 to 2,400 calories during the race. Your stomach must be trained to handle this. Real food (sandwiches, potatoes, fruit) becomes necessary because gels alone will make you nauseous.
Walking uphills is strategy, not weakness
In road marathons, walking feels like giving up. In ultras, walking uphills is a deliberate tactic used by every level of runner, including elites. Power hiking steep uphills conserves your quads for the downhills and keeps your heart rate sustainable over 31 miles.
Back-to-back long runs replace the mega long run
Instead of running 30+ miles in a single session (which would take too long to recover from), ultra training uses back-to-back long runs. Running 15 miles Saturday plus 12 miles Sunday on tired legs simulates the fatigue of ultra distance without the injury risk.
The mental game is completely different
A marathon is about maintaining pace for 3 to 5 hours. A 50K is about problem-solving for 5 to 10 hours. You will have low points. You will want to quit. You will feel nauseous, tired, and emotional. The runners who finish are the ones who keep moving forward through those moments.
Gear becomes critical
For a road marathon, you need shoes and clothes. For a 50K, you likely need a hydration vest, specific trail shoes, a headlamp, emergency supplies, and potentially drop bags. Many races have mandatory gear requirements. Check your race is gear list 4 weeks before and practice running with everything.
16-Week 50K Training Plan
This plan runs 5 to 6 days per week with back-to-back long runs on weekends. One quality session (tempo or hills) per week on Thursday. Recovery weeks every 4th week. Peak week is Week 11 at 55 to 57 miles.
Week 1: Baseline
Easy 5 miles
Easy 6 miles
Rest or cross-train
Tempo: 2mi easy, 3mi at tempo, 2mi easy (7 mi)
Rest
Long run: 14 miles
Recovery run: 6 miles easy
Note
Establish your training rhythm. All easy runs at conversational pace. The Saturday/Sunday back-to-back pattern starts this week.
Week 2: Building
Easy 5 miles
Easy 6 miles
Rest or cross-train
Hills: 2mi easy, 6x90sec hill repeats (jog down), 2mi easy
Rest
Long run: 15 miles (include trails if possible)
Recovery run: 7 miles easy
Note
Hill repeats build the strength you need for trail racing. Run the uphills hard, jog the downhills for recovery. Get on trails for your long run whenever possible.
Week 3: Volume Increase
Easy 6 miles
Easy 6 miles
Rest or cross-train
Tempo: 2mi easy, 4mi at tempo, 2mi easy (8 mi)
Rest
Long run: 16 miles
Recovery run: 8 miles easy
Note
Volume increases modestly. Start practicing your race-day nutrition on the long run. Try eating 200 cal/hour after the first 60 minutes.
Week 4: Recovery
Easy 5 miles
Easy 5 miles
Rest
Easy 5 miles with strides
Rest
Long run: 12 miles easy
Recovery run: 5 miles easy
Note
Recovery week. Drop volume by 25 to 30%. Your body absorbs the training during rest, not during hard weeks. Sleep extra this week if you can.
Week 5: Building Block 2
Easy 6 miles
Easy 6 miles
Rest or cross-train
Hills: 2mi easy, 8x90sec hill repeats, 2mi easy
Rest
Long run: 17 miles (trails)
Back-to-back: 9 miles easy
Note
The back-to-back long runs get serious. Running 9 miles on Sunday on tired legs from Saturday simulates what miles 22 to 31 will feel like on race day.
Week 6: Time on Feet
Easy 6 miles
Easy 7 miles
Rest or cross-train
Tempo: 2mi easy, 4mi at tempo, 2mi easy (8 mi)
Rest
Long run: 18 miles (trails, practice nutrition)
Back-to-back: 10 miles easy
Note
Your first week approaching 50 miles. The 18-mile long run should include your full race-day nutrition plan. If something upsets your stomach, find out now.
Week 7: Pushing Limits
Easy 6 miles
Easy 7 miles
Rest or cross-train
Hills: 2mi easy, 8x2min hill repeats, 2mi easy
Rest
Long run: 20 miles (trails)
Back-to-back: 10 miles easy
Note
Your first 20-miler. This is a significant milestone. Run it at easy pace on trails if possible. Walk the hills. Eat every 30 to 45 minutes. Treat it as a rehearsal.
Week 8: Recovery
Easy 5 miles
Easy 5 miles
Rest
Easy 5 miles with strides
Rest
Long run: 13 miles easy
Recovery run: 6 miles easy
Note
Second recovery week. You have been building for 7 weeks. Let your body repair. Focus on sleep, nutrition, and mobility work.
Week 9: Peak Block Begins
Easy 6 miles
Easy 7 miles
Rest or cross-train
Tempo: 2mi easy, 5mi at tempo, 2mi easy (9 mi)
Rest
Long run: 22 miles (trails, full nutrition practice)
Back-to-back: 10 miles easy
Note
A big week. The 22-mile long run is your primary ultra-specific workout. Run it on terrain similar to your race. Practice walking uphills. Eat early and often.
Week 10: Sustained Volume
Easy 6 miles
Easy 7 miles
Rest or cross-train
Hills: 2mi easy, 6x2min hill repeats, 2mi easy
Rest
Long run: 20 miles (trails)
Back-to-back: 12 miles easy
Note
The back-to-back climbs to 20 plus 12. Running 12 miles on tired legs is the closest simulation to the final miles of a 50K without actually running 50K.
Week 11: Peak Week
Easy 6 miles
Easy 7 miles
Rest or cross-train
Tempo: 2mi easy, 5mi at tempo, 2mi easy (9 mi)
Rest
Long run: 24 to 26 miles (trails, race rehearsal)
Back-to-back: 8 miles very easy
Note
This is your biggest week. The long run is your peak effort. Run it at your planned race pace on race-like terrain. Nail your nutrition. After this, everything gets easier.
Week 12: Recovery
Easy 5 miles
Easy 5 miles
Rest
Easy 5 miles with strides
Rest
Long run: 14 miles easy
Recovery run: 6 miles easy
Note
Critical recovery after peak week. Your body needs this. Do not add extra runs because you feel guilty about the lower mileage. Trust the process.
Week 13: Final Build
Easy 6 miles
Easy 6 miles
Rest or cross-train
Hills: 2mi easy, 6x90sec hills, 2mi easy
Rest
Long run: 18 miles (trails)
Back-to-back: 8 miles easy
Note
A moderate week that keeps fitness sharp without building fatigue. The long run is shorter than peak week but still substantial.
Week 14: Taper Begins
Easy 5 miles
Easy 5 miles
Rest
Easy 5 miles with 6x30sec pickups
Rest
Long run: 14 miles easy
Recovery run: 5 miles easy
Note
Volume drops significantly. You may feel restless, sluggish, or anxious. All are normal taper symptoms. Your body is storing glycogen and repairing tissue.
Week 15: Deep Taper
Easy 4 miles
Easy 4 miles
Rest
Easy 4 miles with strides
Rest
Long run: 10 miles easy
Easy 4 miles
Note
Deep taper. Running feels strange and easy. You may doubt your fitness. This is completely normal. Your fitness is locked in. You cannot gain or lose it in 2 weeks.
Week 16: Race Week
Easy 3 miles
Easy 3 miles with 4x30sec strides
Rest
Easy 2 miles shakeout
Rest
RACE DAY: 50K (31.07 miles)
Rest and recover
Note
Trust your training. Lay out all your gear by Wednesday. Eat familiar foods. Sleep as much as you can. You are ready for this.
Nutrition for a 50K: Eat Early and Often
Nutrition is the single biggest difference between marathon and ultra running. In a marathon, you might consume 300 to 500 calories total. In a 50K, you need 1,000 to 2,400 calories depending on your pace and body size. That is a meal, not a few gels.
The golden rule of ultra nutrition: eat before you are hungry, drink before you are thirsty. By the time you feel hungry during a 50K, you are already behind on calories and it takes 20 to 30 minutes for food to start working. Start eating at mile 3 to 4 and continue every 20 to 30 minutes for the rest of the race.
What to Eat During a 50K
Energy gels (for the first 2 to 3 hours)
PB&J sandwich quarters
Boiled baby potatoes with salt
Banana pieces
Pretzels and potato chips
Energy chews and gummy bears
Sports drink at every aid station
Broth or soup (later in the race when you want something savory)
Calorie Targets by Section
Miles 0 to 5: 100 to 150 cal (easy start)
Miles 5 to 10: 200 to 250 cal/hour
Miles 10 to 15: 250 to 300 cal/hour
Miles 15 to 20: 200 to 300 cal/hour
Miles 20 to 26: 200 to 250 cal/hour (stomach may revolt)
Miles 26 to 31: Whatever you can keep down
Total: 1,200 to 2,400 calories
Hydration: 16 to 24 oz per hour
For a personalized fueling plan, use our race fueling calculator and hydration calculator.
Gear for Your First 50K
Trail running shoes
More aggressive tread than road shoes. Should be well broken in (100+ miles before race day). Consider the terrain: rocky trails need more protection, smooth trails need less.
Hydration vest
Carries two soft flasks (500ml each) on the front chest and has storage for food, phone, and layers. Essential for sections between aid stations. Practice running with it loaded.
Headlamp
Required by most races even for daytime starts. If you are slower than expected, you may be running in the dark. Bring extra batteries. Charge it fully the night before.
Emergency blanket
Lightweight space blanket weighs almost nothing but is required at many ultras. Fits in your vest pocket.
Extra layers
Weather can change dramatically over 5 to 8 hours on a mountain course. Pack a lightweight rain jacket. Consider arm sleeves that can be removed.
Anti-chafe cream
Apply generously to feet, inner thighs, armpits, and anywhere your vest rubs. Reapply at aid stations. Chafing that is minor at mile 5 becomes excruciating at mile 25.
Trekking poles (optional)
Allowed at many ultras and incredibly helpful on steep climbs. Practice with them in training if you plan to use them on race day.
Race Day Strategy: Mile by Mile
Miles 0 to 5
Start very conservatively. The biggest mistake in ultra running is going out too fast. You should feel like you are holding back. Walk the uphills from the start. Eat a small amount (100 cal) at mile 3 to 4.
Miles 5 to 10
Settle into your rhythm. Eat 200 to 300 cal per hour. Drink at every aid station. Take stock of how you feel. This should feel easy. If it does not, slow down.
Miles 10 to 15
You are approaching half marathon distance. Stay on top of nutrition. Switch between gels, real food, and sports drink to prevent flavor fatigue. Walk every uphill.
Miles 15 to 20
The marathon distance is approaching. This is where your back-to-back training pays off. Your legs know how to run on fatigue. Keep eating. Keep drinking. Stay positive.
Miles 20 to 26
The hardest section mentally. You have run a marathon and still have 5 miles to go. Break it into small chunks. Aid station to aid station. Keep moving forward. Walk if you need to.
Miles 26 to 31
You are in uncharted territory. This is why you trained. Every step forward is a step closer to being an ultra runner. The finish line is coming. Enjoy it. You earned this.
Mental Preparation
The physical training gets your body ready. But a 50K is won or lost in your head. At some point during the race, your brain will tell you to stop. It will present very convincing arguments about why you should quit. Your job is to keep moving forward anyway.
Accept that you will have low points
Every ultra runner hits a low point. The nausea, the exhaustion, the "why am I doing this" moment. It passes. Keep eating, keep moving, and wait for the next high point. It always comes.
Break the race into small chunks
Do not think about 31 miles. Think about getting to the next aid station. Then the next one. Then the next one. Thirty-one miles is overwhelming. Three miles is manageable.
Have a "why"
Before race day, write down why you are running this 50K. When mile 22 hits and everything hurts, read it. A strong reason to keep going is the most powerful tool in ultra running.
Remember: everyone around you is hurting too
The runner next to you at mile 25 is just as tired as you are. Ultra running is a shared experience of suffering and perseverance. Talk to other runners. Help each other. The community is what makes ultras special.
Enjoy the experience
You are running 31 miles through nature. Stop at a viewpoint. Take a photo. Thank the volunteers. This is supposed to be fun. If you forget that, you are doing it wrong.
16 Weeks of Territory Conquest
Ultra training means massive mileage across trails, roads, and neighborhoods. Motera turns every training mile into territory on a real map. Your 20-mile long runs carve huge swaths through the map. Your back-to-back weekends create an empire. By race week, your territory will be a monument to 16 weeks of dedication.
Fog of War reveals new areas as you explore further than ever before. Free GPS tracking, territory capture, and leaderboards included.
MoteraFrequently Asked Questions
What is a 50K race?
A 50K is 31.07 miles (50 kilometers). It is the entry-level ultramarathon distance. Most 50K races are run on trails, though some are on roads. Cutoff times are typically generous (7 to 10 hours), and walking is expected and accepted. A 50K is only 4.9 miles longer than a marathon, but the terrain, nutrition demands, and mindset are very different.
How long does it take to train for a 50K?
If you have completed a marathon and are running 30 to 40 miles per week, 16 weeks is sufficient. If you are coming from a half marathon base, add 8 to 12 weeks of building before starting this plan. The total journey from half marathon fitness to 50K race day is roughly 6 to 7 months.
Do I need to run 50K in training?
No. Your longest training run should be 24 to 26 miles. The race-day adrenaline, aid stations, and the taper effect will carry you the remaining distance. Running 50K in training would require too long a recovery and risk injury. Back-to-back long runs (15 miles Saturday plus 12 miles Sunday) simulate the fatigue of ultra distance without the injury risk.
Can I walk during a 50K?
Absolutely, and you should. Walking uphills is a deliberate strategy in ultra running, not a sign of weakness. Even elite ultra runners walk the steepest hills. A common approach is to run everything flat and downhill, and walk everything uphill. This conserves energy and keeps your heart rate manageable over 31 miles.
How much should I eat during a 50K?
Aim for 200 to 300 calories per hour after the first hour. This is significantly more than marathon fueling. Use a mix of gels, real food (PB&J, boiled potatoes, bananas, pretzels), and sports drink. Your stomach will not tolerate gels alone for 5 to 8 hours. Practice eating during long training runs.
What gear do I need for a 50K?
At minimum: trail running shoes, a hydration vest (with two soft flasks or a bladder), and appropriate clothing. Many races also require a headlamp (even for daytime starts, in case you are out longer than expected), an emergency blanket, and a whistle. Check the mandatory gear list for your specific race well before race day.
Is a 50K much harder than a marathon?
The distance is only about 19% longer, but the experience is quite different. Most 50K races are on trails with significant elevation gain, which adds difficulty. The nutrition demands are much higher. The pace is significantly slower. And the mental game shifts from "how fast can I go" to "how can I keep moving forward." Many runners find the ultra community more welcoming and the experience more enjoyable than road marathons.
What if I am too slow for a 50K?
Most 50K races have very generous cutoff times of 7 to 10 hours. If you can run/walk a marathon in under 5.5 hours, you can almost certainly finish a 50K within the cutoff. Ultra running is not about speed. It is about forward progress and problem-solving. There is no "too slow" if you make the cutoffs.
