Two days of continuous decisions
48-Hour Races
A two-day fixed-time race where sleep, recovery choices, and the second night become central parts of the plan.
Cover photo: Jérémie Crausaz / Unsplash
How the Format Works
A 48-hour race extends the familiar fixed-time model across two full day-night cycles. Runners accumulate distance on a measured course while choosing when to walk, eat, change, rest, or sleep.
The second night changes the problem. Early pacing errors, food fatigue, foot damage, and sleep loss can compound, so the best plan is a set of tested options rather than one rigid mileage or sleep schedule.
Checked figures
Distances that define the format
The 48-hour records are separate performances, not twice the 24-hour records. Their ratio does not isolate the effects of sleep, feet, digestion, conditions or field strength.
| Measure | Figure |
|---|---|
| Men's IAU world record | 485.099 km, Matthieu Bonne, Pabianice, 30 May–1 June 2025 |
| Women's IAU world record | 436.371 km, Patrycja Bereznowska, same race |
| Those records as average speed | 10.1 km/h men, 9.1 km/h women, over the full 48 hours |
| Recorded performances, 2025 | 2,462 in the DUV worldwide distance table |
| 48 heures de Royan, October 2025 | median 201.1 km, middle 50% 161.4–222.0 km, 38 results |
| Across the Years 48h, December 2025 | median 161.2 km, middle 50% 106.7–178.2 km, 53 results |
The Across the Years median is near 100 miles, but a result list alone does not establish why runners stopped. Stopped time is part of the result: a 200 km goal with four hours stopped needs 13:12 per kilometre while moving, and with six hours stopped 12:36.
Sources: IAU records list; DUV results: 48 heures de Royan, October 2025; DUV results: Across the Years 48h, December 2025; DUV 2025 distance table, via the timed-format comparison.
Curated preparation path
Learn, Train, and Plan
1. Understand the Format
Learn what the extra day changes and compare it with shorter and longer timed races.
48-Hour Races Explained
Rules, sleep, pacing, common course setups, and safety considerations.
Guide24-Hour vs 48-Hour vs 6-Day
Compare the practical demands of the three core fixed-time formats.
AnswerCan You Sleep During an Ultramarathon?
How rules, duration, safety, and individual goals shape rest decisions.
2. Build the Training Plan
Prepare for durable movement and logistics without using deliberate sleep deprivation as routine training.
How to Train for a 48-Hour Race
An adaptable framework for volume, back-to-back work, walking, and race rehearsals.
AnswerHow Long Does Ultramarathon Training Take?
Set a realistic build-up length before committing to a two-day race date.
ToolMultiday Pace Calculator
Test moving-time, sleep, break, and average-distance scenarios.
3. Plan Both Nights
Create options for alertness, sleep, pacing, food, and support before fatigue narrows your judgment.
Sleep Strategy for Multiday Races
Plan flexible rest options and clear triggers for stopping safely.
GuideThe Second Night Survival Guide
Recognize the second-night risks and simplify decisions before they arrive.
GuideCrew and Aid Station Strategy
Design a repeatable support flow that works when communication gets harder.
4. Fuel and Protect
Use adaptable food, fluid, footwear, and foot-care systems across changing conditions.
Hydration and Sodium
Use thirst as a starting signal and understand the danger of forced overdrinking.
GuideBlister Prevention
Handle moisture, friction, and fit before a second day makes them race-ending.
AnswerWhat Do Ultrarunners Eat?
Compare real-food and packaged options that still work on the second day.
Curated race directory
Active and Upcoming 48-Hour Events
9 matching events as of Nov 9, 2026; event source reviews dated August 18, 2026 – November 5, 2026. 10 past editions remain in the directory archive.
Fat Ox Endurance Runs
Goodyear, Arizona, USA
A fixed-time festival on a certified 0.988178-mile concrete loop, headlined by the 48-hour race and 2026 USATF 24-Hour Championships.
View verified race details →Across the Years
Peoria, Arizona, USA
A New Year fixed-time festival on a 1.42-mile dirt and paved loop at Peoria Sports Complex, with a 6-day race, rolling-start 72- to 6-hour races and 100- and 200-mile options.
View verified race details →Jackalope Jam
Cat Spring, Texas, USA
A timed ultrarunning festival at 7IL Ranch, where runners repeat a flat two-mile out-and-back and can choose events lasting up to 100 hours.
View verified race details →Jackpot Ultras
Cornerstone Park, Henderson, Nevada, USA
Aravaipa’s timed-race festival at Cornerstone Park offers 48-hour and 24-hour races alongside shorter timed events and fixed distances.
View verified race details →Taipei Ultramarathon
Xinsheng Park, Taipei, Taiwan
A Taipei ultrarunning festival with 48-, 24-, 12- and 6-hour races at Xinsheng Park, plus separate fixed-distance and relay competitions.
View verified race details →Festival de Ultrafondo — Gran Premio Ciudad de Burjassot
Burjassot, Valencia, Spain
The seventh Burjassot ultradistance festival includes a 48-hour road race and a separate 24-hour race, both listed with IAU Bronze Labels, near Valencia.
View verified race details →NZ Ultramarathon Festival — 6 Day
Hagley Park, Christchurch, New Zealand
A fully catered six-day race on a flat 1.9464 km park loop, part of a ten-day Christchurch festival with 72-, 48-, and 24-hour options.
View verified race details →Sommer 24+48 Stunden Lauf Freudenstadt-Grüntal
Freudenstadt-Grüntal, Germany
A summer timed race in the Black Forest, adding a first 48-hour edition alongside the third Sommer24hLauf in 2027.
View verified race details →GOMU 48-Hour World Championship
Skanderborg, Denmark
The 2027 Global Organization of Multi-Day Ultramarathoners 48-hour world championship, hosted by Skanderborg Ultra in Denmark.
View verified race details →Dates, entry status, routes, and rules can change. Use each event page's official organizer links before registration or travel. Format preparation paths were reviewed October 23, 2026.
48-Hour FAQs
Should you practice running through the night?
Practice lights, layers and familiar food on a safe outing that includes darkness and fits your existing training. It need not last 6–8 hours or finish at 02:00. Arrange an easy exit and normal recovery; deliberately becoming sleepy is not a prerequisite.
How far do runners go in a 48-hour race?
In two open 2025 fields, medians were about 201 km at Royan (38 results) and 161 km at Across the Years (53 results). Our default first 48-hour target is 160 km (100 miles), with 200 km as the stretch; set it lower if your build was short or interrupted. The IAU world records are 485.099 km (Matthieu Bonne, 2025) and 436.371 km (Patrycja Bereznowska, 2025).
Compare Related Formats
24-Hour Races
A fixed-time race where the clock runs for one full day and every completed lap or measured distance counts.
6-Day Races
A 144-hour fixed-time event where sustainable routines and recovery choices matter across nearly a full week.
Backyard Ultras
A last-person-standing format built around one 6.7056 km loop every hour, on the hour, until one runner completes a yard that nobody else finishes.