Ultimate Guide To Ultra Running 2026

Q: How many calories should you eat during an ultra marathon?

Current research recommends 200 to 400 calories per hour during an ultra marathon, with 60 to 90 grams of carbohydrates per hour as the baseline. Elite ultra runners average around 70 grams of carbs per hour. Using a glucose to fructose ratio of 2 to 1 or 1 to 0.8 allows your body to absorb more carbohydrate through dual transport pathways in the gut. Start at the lower end and increase gradually. Practice your race nutrition on training runs because gut training is as important as leg training.

Q: Is it OK to walk during an ultra marathon?

Yes. Walking is not just allowed in ultra marathons, it is expected and strategic. Almost every ultra runner walks at some point during a race, particularly on steep climbs, through aid stations, and in the later miles when fatigue accumulates. Many experienced ultra runners use a run walk strategy from the start, alternating between running flat and downhill sections and walking uphills. This approach conserves energy and often produces faster overall finish times than trying to run everything.

Q: What gear do you need for an ultra marathon?

The essentials are trail running shoes with good traction and cushioning, a hydration vest or pack that carries at least 1.5 liters of fluid, a headlamp rated for at least 300 lumens if running through darkness, anti chafe cream, multiple layers for changing weather conditions, and a GPS watch with battery life that exceeds your expected finish time. Most trail ultras have mandatory gear lists that you must carry including an emergency blanket, whistle, and waterproof jacket. Check your race requirements well before race day.

Q: What is the best distance for your first ultra marathon?

A 50K (31 miles) is the standard entry point into ultra running. It is only 5 miles longer than a marathon and most runners with marathon experience can train for a 50K in 12 to 16 weeks. Choose a 50K with generous cut off times, good aid station support, and moderate terrain for your first attempt. Some runners skip 50K and go straight to 50 miles, but this significantly increases the training commitment and the risk of a negative experience. A successful and enjoyable first ultra will motivate you far more than a painful one.

What Nobody Tells You About Running Your First Ultra

You have done the 5K, the half, the full marathon. You crossed each finish line thinking “that was hard but I want more.” Now you are staring at a 50K or 50 mile entry form wondering if you are ready. Here is what I can tell you after running ultras on trails in Manitoba and racing distances that once seemed impossible: you are closer to ready than you think, and the gap between marathon and ultra is more mental and logistical than physical.

Ultra running is any distance beyond the standard marathon of 26.2 miles (42.195 km). The most popular distances are 50K (31 miles), 50 miles (80.5 km), 100K (62 miles), and 100 miles (161 km). Some races go even further. The Sri Chinmoy Self-Transcendence 3,100, held each summer in Queens, New York, covers 3,100 miles and is the longest certified footrace in the world. You do not need to start there.

What This Guide Covers

Training: How to build from marathon fitness to ultra fitness in 6 months
Nutrition: Evidence based fueling at 60 to 90g carbs per hour (updated 2026 research)
Race distances: What to expect at 50K, 50 miles, 100K, and 100 miles
Strength and mobility: The exercises that prevent ultra specific injuries
Mental preparation: How to keep going when your body says stop
Gear: The essentials including shoes, hydration, watches, and headlamps
Recovery: How long to rest and what to do after the race

Jump to:

Pick Your Distance Training Plan Nutrition Strength Mental Game Gear List Recovery FAQ Last Updated: April 2026

Choose Your Challenge

Ultra Marathon Distances Explained

Each distance has a different character, different training demands, and a different relationship with walking, nutrition, and gear. Tap the distance you are considering to see what to expect.

Select Your Distance

50K 50 Mile 100K 100 Mile

Best first ultra · 12 to 16 week build

50K (31 miles)

Only 5 miles longer than a marathon. If you can run a marathon, you can run a 50K with 12 to 16 weeks of targeted training. The biggest difference is that most 50K races are on trails, which means uneven terrain, elevation gain, and a slower pace than road racing. You will walk the steep uphills and that is completely normal. Expect a finish time roughly 30 to 60 minutes longer than your marathon time on easy terrain, or 1 to 2 hours longer on technical trail courses. Weekly mileage during training: 35 to 50 miles per week with a peak long run of 22 to 26 miles.

The step up · 16 to 20 week build

50 Miles (80.5 km)

This is where ultra running truly begins. Fifty miles takes most runners 8 to 14 hours depending on terrain and fitness. You will run through multiple meal times and your body will experience genuine fatigue that a marathon does not touch. Nutrition becomes critical at this distance because you cannot outrun a calorie deficit over 10+ hours. Training requires 40 to 60 miles per week with back to back long runs on weekends (20 miles Saturday, 15 miles Sunday) to practice running on tired legs. Your longest single training run should be 30 to 35 miles.

Serious commitment · 20 to 24 week build

100K (62 miles)

The 100K is a full day event for most runners, taking 12 to 20 hours. You will likely run through darkness and need a headlamp. Sleep deprivation becomes a factor. Gastrointestinal issues affect the majority of runners at this distance, which makes practiced and disciplined nutrition absolutely essential. Training requires 50 to 70 miles per week at peak with several back to back weekends of 25+ miles on day one and 15+ miles on day two. Strength training and injury prevention become non-negotiable at this training volume.

The big one · 6+ month build

100 Miles (161 km)

The hundred miler is the defining distance of ultra running. Most runners take 20 to 30+ hours and will experience darkness, extreme fatigue, emotional highs and lows, potential hallucinations from sleep deprivation, and GI distress. You will walk significant portions of this race and that is expected. Training requires 6+ months of dedicated preparation with peak weeks of 60 to 80+ miles, multiple 30+ mile long runs, and meticulous race day planning for nutrition, crew support, gear changes, and pacing. Your longest training run should be 40 to 50 miles, but back to back weekends matter more than any single long run.

Building Your Base

How to Train for an Ultra Marathon

A 2024 case study published in the International Journal of Sports Physiology and Performance examined the training regimen of an elite ultra runner who broke 8 world records. The findings reinforced what experienced coaches have known: ultra marathon training should include high volume running at varied paces and intensity with cross training to avoid injuries. The principles scale down to recreational ultra runners too. Here is the framework.

Build a Marathon Base First

You need at least 6 months of consistent running at 30+ miles per week before starting an ultra specific training plan. If you have not run a marathon yet, do that first. Your marathon experience builds the aerobic engine, the mental resilience, and the logistical skills (nutrition, pacing, gear) that ultra running amplifies.

Prerequisite · 30+ mpw for 6 months minimum

Follow a 3 Week Build, 1 Week Recovery Cycle

Increase your weekly mileage for three consecutive weeks, then cut back 20 to 30 percent for one recovery week. This periodization allows your body to adapt to each increase in load before adding more. It is the same principle as marathon training but applied over a longer timeline with higher peak volumes.

Structure · Prevents overtraining and overuse injuries

Back to Back Long Runs Are the Key Workout

Instead of a single 30 mile training run, do 20 miles on Saturday and 15 miles on Sunday. Running on tired legs from the previous day simulates the fatigue you will experience in the later miles of your ultra. This is the single most important ultra specific workout and it should appear in your plan every 2 to 3 weeks during the build phase.

Critical workout · Every 2 to 3 weeks

Keep One Speed Session Per Week

Ultra running is slow, but speed work still matters. One tempo run or interval session per week improves your running economy, which means you burn less energy at any given pace. A more efficient stride over 50 miles adds up to significantly less fatigue by the end. Keep speed sessions short and recovery focused. You are not training for a 5K PR.

Weekly · Tempo or intervals

Train on the Surface You Will Race On

If your race is on trails, train on trails. If it involves significant elevation, train on hills. Downhill running causes more muscle damage than uphill running because of the eccentric loading on your quadriceps, and runners who do not practice downhill running in training pay for it on race day. If your race involves night running, do at least two training runs in darkness with your headlamp.

Specificity · Match terrain, elevation, conditions

Taper 2 to 3 Weeks Before Race Day

Reduce your mileage by 40 to 50 percent in the final 2 to 3 weeks before your ultra. Maintain some intensity (short tempo efforts) but cut volume significantly. This allows your body to repair, rebuild glycogen stores, and arrive at the start line fresh. The fitness is already in the bank. The taper is about letting it out.

Pre-race · 2 to 3 weeks out

The most common training mistake: Doing a single epic long run (35+ miles) instead of consistent back to back weekends. One very long run at extreme distance increases injury risk dramatically and requires extended recovery that disrupts the rest of your training week. Back to back long runs of moderate distance deliver the same adaptation with far less risk.

Fueling the Engine

Ultra Marathon Nutrition: What the Science Says in 2026

Nutrition is the difference between finishing strong and not finishing at all. A 2024 study from the TorTour de Ruhr (one of Europe’s longest non-stop ultras) found that ultramarathon running caused large energy deficits and significant hormonal and muscle damage responses that increased with race distance. The 230 km runners showed the most pronounced metabolic strain. The researchers concluded that individualized, distance-specific fueling strategies are essential, particularly for recreational ultra runners. Here is what the current evidence recommends.

Before the Race: Carb Loading

In the 2 to 3 days before your ultra, increase your carbohydrate intake to 8 to 12 grams per kilogram of body weight per day. For a 75 kg (165 lb) runner, that means 600 to 900 grams of carbs per day. This is a lot of pasta, rice, oatmeal, and bread. Taper your training during this period so you are storing glycogen rather than burning it. Your last big meal should be the night before the race. On race morning, eat a familiar carbohydrate rich meal 2 to 4 hours before the start.

During the Race: The 60 to 90g Rule

Current research recommends 60 to 90 grams of carbohydrate per hour during ultra endurance events. Elite ultra finishers average around 70 grams per hour, while runners who consume less than 45 grams per hour are significantly more likely to DNF. The key is using a mix of glucose and fructose (a 2:1 or 1:0.8 ratio), because these two sugars are absorbed through different transporters in your gut, allowing a higher total absorption rate than either sugar alone.

In practical terms, 60 to 90 grams of carbs per hour means roughly 240 to 360 calories per hour from carbohydrate sources. This can come from gels, chews, sports drinks, and real food like bananas, rice balls, PB&J sandwiches, and potatoes. For races lasting 8+ hours, most runners need real food in addition to gels because flavor fatigue and GI distress from consuming only sweet gels is a real and common problem.

What the research says: The International Society of Sports Nutrition position stand on ultra marathon nutrition states that the central aim of any ultra marathon training program should be to maximize capacity for fat metabolism while maintaining the ability to use carbohydrate at higher intensities. Training your gut to handle race day nutrition is as important as training your legs.

✓ Race Day Nutrition Rules

60 to 90g carbs per hour, starting from the first hour
Mix glucose and fructose sources (dual transport)
Eat real food after 6+ hours (sandwiches, potatoes, broth)
Practice your exact race nutrition on training long runs
Sip fluids consistently: 500 to 750ml per hour
Take electrolytes, especially sodium, in hot conditions

✗ Common Nutrition Mistakes

Trying new food or gels on race day
Waiting until you feel hungry to start eating (too late)
Relying only on sweet gels for 10+ hour races
Drinking only water without electrolytes
Following a keto diet during ultra racing (impairs performance)
Sitting at aid stations for 10+ minutes (muscles cool, harder to restart)

Electrolytes matter: Sodium, potassium, and magnesium are lost through sweat. In races over 4 hours, plain water is not enough. Use electrolyte tablets, sports drinks with sodium, or salt capsules. Hyponatremia (dangerously low blood sodium from drinking too much plain water) is a real risk in long ultras, especially in hot conditions.

Injury Prevention

Strength Training for Ultra Runners

Strength training is not optional for ultra runners. The repetitive loading of 50 to 100 miles of running demands resilient muscles, tendons, and joints that can absorb forces hour after hour. Research consistently shows that runners who incorporate strength training experience fewer overuse injuries, better running economy, and stronger performance in the later miles of races when fatigue sets in.

Runner doing single leg squats for strength training

Focus on these muscle groups: glutes (hip stability on uneven terrain), quadriceps (absorbing downhill impact), calves and Achilles (propulsion and shock absorption), and core (maintaining running form under fatigue). Two sessions per week of 20 to 30 minutes is enough. During peak mileage weeks, reduce strength volume but do not eliminate it entirely.

Key exercises include single leg squats, Romanian deadlifts, calf raises (slow and controlled), hip bridges, lateral band walks, planks, and Bulgarian split squats. If your race has significant downhill sections, add eccentric quad work like slow step downs off a box. For mobility, see our warm up guide for dynamic stretching routines, and always warm up before running. Never do heavy strength training the day before a long run.

The Other 50%

Mental Preparation for Ultra Running

Every ultra runner hits a low point. A stretch of miles where your body hurts, your stomach rebels, you are exhausted, and the finish line feels impossibly far away. The runners who finish are not always the fittest. They are the ones who have a strategy for getting through those dark patches. Here is what works.

Break the Race Into Segments

Do not think about finishing 100 miles. Think about getting to the next aid station, 5 to 8 miles away. When you arrive, think about the next one. Each segment is manageable. The total distance is not. Every ultra finisher will tell you the same thing: you run it one aid station at a time.

Visualize the Course in Advance

Study the elevation profile. Watch videos from previous years. Look at photos of the terrain and the aid stations. Knowing what is coming reduces the mental shock of encountering difficult sections. If you know the big climb is at mile 40, you can prepare for it mentally rather than being ambushed by it.

Accept the Low Points in Advance

You will feel terrible at some point. That is not a sign that the race is over. It is a sign that you are in an ultra. Low points pass if you keep eating, keep drinking, and keep moving forward. Walk if you need to. Sit for 2 minutes at an aid station if you need to. But keep going. The runners who DNF most often quit during a low point that would have passed within 30 minutes if they had kept moving.

Have a “Why” That Matters to You

At mile 70 of a hundred miler, “because it would be cool” is not going to get you up a hill. But “because I told my daughter I would finish” might. “Because I started running after my diagnosis and this proves I am still here” will. Your reason does not need to be dramatic, but it needs to be real and personal. Know it before the race starts.

What to Bring

Essential Gear for Ultra Running

Ultra gear is different from marathon gear because you are out longer, conditions change, and you need to be more self sufficient between aid stations. Most trail ultras have mandatory gear lists that you must carry at all times. Check your specific race requirements early and train with the gear you will race in.

The Non-Negotiables

Trail shoes: You need trail specific shoes with grip, protection, and enough cushioning for the distance. Do not run trails in road shoes (I learned that lesson the hard way with a sprained ankle). See our trail shoe reviews or take the Shoe Finder.

Hydration vest: A running vest that carries at least 1.5 liters of fluid plus storage for nutrition, layers, and mandatory gear. Train in your vest on long runs so it fits properly under load.

GPS watch: You need a watch with battery life that exceeds your expected finish time. For 50K, any modern GPS watch works. For 100 miles, you need a watch like the Garmin Enduro 3 or Coros Apex 4 with 40+ hours of GPS battery. See our ultra watch guide or the marathon watch guide for specific recommendations.

Headlamp: Any race that involves running through darkness requires a headlamp. Look for at least 300 lumens with a battery life that matches your expected dark hours. See our headlamp guide.

Anti chafe: Body Glide, Squirrel’s Nut Butter, or similar anti chafe products applied to inner thighs, feet, underarms, and anywhere your vest contacts skin. Reapply at aid stations. Chafing that is minor at mile 10 becomes debilitating at mile 40.

Layers: Weather changes dramatically during a 12 to 30 hour event. Carry a lightweight waterproof jacket, arm sleeves or a long sleeve base layer, and consider gloves for cold night sections.

After the Finish Line

How to Recover After an Ultra Marathon

The common guideline is one recovery day per 10 km or 10 miles of race distance. For a 50K, that means about 5 days of very easy activity. For a 100 miler, 2 to 4 weeks. Ultra running causes deep muscle and tendon damage that takes significantly longer to heal than the surface level soreness you feel the day after. The fact that your legs stop hurting after a week does not mean the tissue has fully recovered.

During your recovery period, stay active with walking, easy swimming, or gentle cycling but do not run until the soreness has fully cleared. Continue eating a nutrient dense diet with adequate protein (1.6 to 2.0 grams per kilogram of body weight per day) to support tissue repair. Sleep is when the real rebuilding happens, so prioritize it. Do not sign up for another race until you have fully recovered from the last one, no matter how motivated you feel in the days after finishing.

Post-race nutrition tip: A 2024 study found that cloudy apple juice, rich in polyphenols, supports gut barrier recovery after ultra endurance events better than pure sugar drinks. Include polyphenol rich foods like berries, pomegranate juice, dark chocolate, and green tea in your recovery nutrition to help your gut microbiome recover alongside your muscles.

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See our guide to the most popular ultras you should know about in 2026.

Common Questions

FAQ

How do you train for your first ultra marathon?

Start with a solid marathon base of at least 30 miles per week for several months. Build to a 6 month ultra specific training block that includes weekly long runs, back to back long runs on weekends, one speed session per week, strength training twice a week, and progressive mileage increases following a 3 week build and 1 week recovery cycle. Your longest training run should be 60 to 70 percent of race distance for a 50K and 30 to 40 percent for a 100 miler.

How many calories should you eat during an ultra marathon?

Current research recommends 200 to 400 calories per hour, with 60 to 90 grams of carbohydrates per hour as the baseline. Elite ultra runners average around 70 grams of carbs per hour. Using a glucose to fructose mix allows your body to absorb more carbohydrate. Start at the lower end and increase gradually. Practice your race nutrition on training runs.

Is it OK to walk during an ultra marathon?

Yes. Walking is expected and strategic. Almost every ultra runner walks at some point, particularly on steep climbs, through aid stations, and in the later miles. Many experienced runners use a run walk strategy from the start, running flats and downhills, walking uphills. This conserves energy and often produces faster finish times than trying to run everything.

How long does it take to recover from an ultra marathon?

A common guideline is one recovery day per 10 kilometers or 10 miles of race distance. For a 50K that means roughly 5 days. For a 100 miler, 2 to 4 weeks. Recovery should include walking, swimming, adequate sleep, healthy nutrition, and a gradual return to running volume.

What is the best distance for your first ultra marathon?

A 50K (31 miles) is the standard entry point. It is only 5 miles longer than a marathon and most runners with marathon experience can train for one in 12 to 16 weeks. Choose a 50K with generous cut off times, good aid station support, and moderate terrain for your first attempt.

What gear do you need for an ultra marathon?

The essentials are trail running shoes, a hydration vest, a headlamp (if running through darkness), anti chafe cream, multiple layers for changing weather, and a GPS watch with battery life exceeding your finish time. Most trail ultras have mandatory gear lists including emergency blanket, whistle, and waterproof jacket. Check your race requirements early.

Can you run an ultra marathon on a keto diet?

The ISSN position stand on ultra marathon nutrition cautions against sustained ketogenic diets for performance. While keto may enhance fat oxidation, it can impair the ability to perform at higher intensities due to reduced carbohydrate availability. The high fat content can also cause GI distress during running. Most evidence supports a periodized carbohydrate approach where fat adaptation is built during training but carbohydrate is still used strategically during racing.

What pace do ultra marathoners run?

Slower than you expect. Average pace for a 50K on trails is roughly 10 to 13 minutes per mile for recreational runners. For a 100 miler, average paces of 13 to 18 minutes per mile (including walking) are common. The key is starting conservatively and maintaining a sustainable effort. If you start too fast in an ultra, the back half will punish you far more than it would in a marathon.

Quick Answer

How to Get Started

Step 1: Run a marathon first if you have not already. Build a base of 30+ miles per week for at least 6 months.

Step 2: Sign up for a 50K with generous cut off times and good aid station support. Check popular ultras or UltraSignup.

Step 3: Follow a 12 to 16 week training plan built around back to back long runs, one speed session per week, and twice weekly strength training.

Step 4: Practice your race nutrition on every long run. Aim for 60 to 90 grams of carbs per hour using a glucose and fructose mix.

Step 5: Get the right gear: trail shoes, hydration vest, GPS watch with long battery, and a headlamp. Train with all of it.

Sources: Byrne, Lynch & Mokha, “Training Regimen of an Elite Ultramarathon Runner,” Int J Sports Physiol Perform, 2024. Berger et al., “Limits of Ultra: Towards an Interdisciplinary Understanding of Ultra-Endurance Running Performance,” Sports Medicine, 2024. Tiller et al., “International Society of Sports Nutrition Position Stand: Nutritional Considerations for Single-Stage Ultra-Marathon Training and Racing,” J Int Soc Sports Nutr, 2019. Nutrients, “Does Distance Matter? Metabolic and Muscular Challenges of a Non-Stop Ultramarathon,” 2025.

Ultimate guide to Ultra Running 2026

What Nobody Tells You About Running Your First Ultra