The Practical Guide to Ultra Endurance
Learn to Go Farther
Than One Day
Find a race, adapt a training framework, and build a pacing or crew plan for 24-hour, 48-hour, six-day, backyard, and stage events.
Around the race calendar
Races & Results
Calendar snapshot: . Race windows follow listed dates; organizers provide live updates.
Racing now
6 listedStarted · Through
MDS 120 Jordan
Wadi Rum, Jordan
Stage Race
Follow organizer updates ↗Started · Through
Javelina Jundred — 100 Mile
McDowell Mountain Regional Park, Arizona, USA
Fixed-Distance
Follow organizer updates ↗Started · Through
Ozark Trail 100 Mile Endurance Run
Mark Twain National Forest to Steelville, Missouri, USA
Fixed-Distance
Follow organizer updates ↗
Next 30 days
28 racesStarting after today, through Dec 1, 2026.
Ultra-Trail Shudao by UTMB
Guangyuan, Sichuan, China
Fixed-Distance
Arrowtown Backyard Ultra
Butler Green, Arrowtown, Otago, New Zealand
Backyard Ultra
Big Tex Backyard Ultra
Stephen F. Austin State Park, San Felipe, Texas, USA
Backyard Ultra
Pinhoti 100
Pine Glen Campground to Sylacauga, Alabama, USA
Fixed-Distance
Latest results
Kullamannen Ultra 100 Miles
Juuso Simpanen won his second Kullamannen 100-miler in 15:39:15, 4:17 ahead of Baptiste Derouin; Anna Carlsson won the women’s race in 16:44:26, fifth overall.
Read results →Mallorca by UTMB
Lambert Santelli won the Serra de Tramuntana in 14:38:02, 42 minutes clear of Jeremy Lenormand; Maite Maiora Elizondo won the women’s race in 18:01:27, 17th overall.
Read results →ISOPOL Super24
The published 24-hour timing results list Octavian Ciorescu first with 249.561 km and Szilvia Hudák first woman with 204.765 km; final confirmation remains pending.
Read results →
What Are You Planning?
Choose a format →
Compare the clock, course, support, and withdrawal options before you enter.
Find your next race →
Search by place, then filter race format, region, and terrain. Official links let you check entry details.
Build a pacing scenario →
For example: 120 km in 24 hours with two hours stopped leaves 22 moving hours, or 11:00 per km. Change the assumptions to see the effect.
The pacing example illustrates arithmetic, not a recommended race target. Explore all planning tools →
Beyond the marathon
What Is Multiday Running?
Multiday running covers events whose clock or stages extend through day-night cycles or across several days. From 24-hour tracks to week-long stage races, the format makes walking, food, rest, equipment, support, and changing conditions part of the plan.
New to the broader sport? Start with how long an ultramarathon is and how fixed-distance, timed, and multiday formats differ.
Read the full introduction →
Not Just Speed
Pacing, food tolerance, rest, equipment, and problem-solving can matter alongside fitness.
Mental Skills Matter
Boredom, motivation, and problem-solving can influence persistence alongside physical fitness.
A Community Sport
Crews, pacers, aid station volunteers, and fellow runners all shape the race.
Find your format
Choose Your Path
Multiday running comes in many formats. Each demands different preparation, strategy, and gear. Compare the rules, support, withdrawal plan, and skills you are prepared to practice.
Selected guides
Featured Guides
How to Train for Your First 24-Hour Race
Read guide →Backyard Ultras Explained: Rules, Records, and Safety
Read guide →24-Hour Race Pacing Strategy
Read guide →Backyard Ultra Race Strategy
Read guide →What to Eat During a 24-Hour Race
Read guide →Blister Prevention for Ultramarathons
Read guide →From the Research
Our guides draw on current exercise physiology, biomechanics, and sports psychology research where evidence exists, with uncertainty and study limits explained. Read our editorial policy for how sources, illustrative examples, and professional review are distinguished.
Odds ratio linking higher boredom with an action crisis in one mixed solo/relay 24-hour study
A better race-day rule
Persistence Never Outranks Safety
Ordinary fatigue and doubt may pass. Confusion, involuntary sleep, loss of coordination, collapse, chest pain, severe breathing difficulty, or repeated vomiting call for a stop and medical assessment—not a motivational slogan.