What is an ultramarathon, and who is it for?
An ultramarathon is any footrace longer than the marathon's 42.195 kilometres, from 50km road races to 100-mile mountain trails and events where you run as far as you can in a set time. Ultras are usually slower, more sociable and more about eating, walking and problem-solving than people expect, which is why they suit patient, curious runners more than fast ones.
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The word sounds extreme, and some ultras are. But plenty of them are long days out with snacks, scenery and a lot more walking than anyone admits in the pub afterwards.
The definition
The Wikipedia entry on ultramarathons defines one simply as a footrace longer than the traditional marathon distance of 42.195 kilometres. The common distances it lists are 50km, 50 miles, 100km and 100 miles, with some events going far beyond that.
World Athletics describes two kinds of ultra: races over a set distance, such as 50km or 100km, and races over a set time, such as 6 or 24 hours, where the winner is whoever covers the most ground. It names the International Association of Ultrarunners as the worldwide governing body for ultramarathon events.
So technically, a 43km run counts. In practice, 50km is where most people's first ultra begins.
Road, track and trail
World Athletics describes ultras on roads, on tracks and on trails, plus races that mix terrain or run over several days.
- Road ultras are the closest cousin of the marathon: measured courses, steady running, often big fields.
- Track and timed events happen on a loop, sometimes for 24 hours. They sound mad and are often very social, because you see the same people every few minutes.
- Trail and mountain ultras are what most people picture now: forest paths, ridges, climbs and descents, where the distance matters less than the terrain and the time on your feet.
Why they are slower and stranger than you think
On a long trail ultra, almost everyone walks the steep climbs. It is not giving up; it is tactics. Pace is closer to a brisk hike punctuated by running than to a marathon effort.
Eating becomes a skill. Aid stations, which the Wikipedia entry notes most ultras have, are part buffet, part pit stop: you will see people eating crisps, fruit, soup and sandwiches. Managing food, water, feet, layers and mood across a long day is a large part of what ultrarunners enjoy. It feels more like an expedition than a race.
The atmosphere is usually relaxed. When you are going to be out for eight or more hours, there is time to talk to strangers, and plenty of people do.
Who is it for?
Not just elite athletes, but also not a casual first race. Ultras tend to suit people who:
- Enjoy long days outside more than fast times.
- Like solving problems on the move: blisters, weather, navigation, appetite.
- Already run comfortably for a few hours, usually having done marathons or long trail runs first.
- Are patient. Ultras reward steady effort and punish heroics in the first hour.
If you are curious, the gentle route in is to make your long walks and runs longer and hillier, try trail running (our trail running guide covers the basics), and look for a friendly 50km with generous cut-off times. Many people walk a large part of their first ultra, and that is completely normal.
If the question in your head is really "why would anyone do this?", our piece on why people run marathons covers a lot of the same pull.
FAQ
Do you have to run the whole way?
No. Walking, especially uphill, is standard practice in trail ultras, including for experienced runners.
Is a 50km harder than a marathon?
It is longer, but a hilly trail 50km is often run at a gentler pace than a road marathon, so it feels different rather than simply harder. The terrain matters more than the extra eight kilometres.
Do I need special kit?
Trail ultras often have a compulsory kit list, such as a waterproof jacket, a phone, a cup and a small first-aid kit, set by the organiser. Read it early and practise carrying it.
What is a timed ultra?
An event where the clock is fixed and the distance is not: you cover as much ground as you can in, say, 6 or 24 hours, usually on a short loop.
Sources
Written by the Zestasy editors. General information for curious adults, not medical, nutrition or training advice.