Overview

An ultra marathon is any race longer than 26.2 miles (42.2 km). The most common entry-level distance is 50K (31 miles) — just 5 miles further than a marathon, but a completely different experience. Ultra running isn't about speed — it's about endurance, problem-solving, and resilience.

Golden Rule: In an ultra, the race doesn't start until the marathon distance. Everything before that is a warm-up.

Are You Ready?

Before attempting an ultra, you should be able to tick most of these:

Prerequisite	Why
Completed at least one marathon	You need to know what 42 km feels like
Comfortable running 50+ km per week	Your body needs to handle the mileage
Experience with back-to-back long runs	Ultras require running on tired legs
Good nutrition and fuelling strategy	You'll be eating and drinking for hours
Mental resilience	There will be low points — you need to push through them

Ultra Distances

Distance	Miles	Typical Finish Time (First-Timer)	Notes
50K	31 mi	5–7 hours	Great first ultra — only 9 km further than a marathon
50 miles	50 mi	9–14 hours	A proper test of endurance
100K	62 mi	12–20 hours	Serious undertaking — requires night running
100 miles	100 mi	24–36 hours	The pinnacle — requires sleep strategy and crew

Training for Your First 50K

The 12-Week Plan Structure

Build on your marathon fitness. You don't need to run 50 km in training — you need to build time on feet.

Week Block	Weekly Mileage	Long Run	Key Sessions
Weeks 1–4	50–60 km	25–30 km	1 speed session, 1 back-to-back weekend
Weeks 5–8	60–75 km	30–38 km	1 tempo run, 1 back-to-back weekend
Weeks 9–10	65–75 km	35–40 km	Race-specific sessions, kit testing
Week 11	50 km	20 km	Taper begins
Week 12	30 km	Race Day	50K ultra

Back-to-Back Long Runs

The single most important ultra training session. Run long on Saturday, then run again on Sunday on tired legs.

Saturday	Sunday
25 km at easy pace	15 km at easy pace
30 km at easy pace	18 km at easy pace
35 km at easy pace	15 km at easy pace

Purpose: This teaches your body to run when fatigued — exactly what an ultra demands.

Ultra Nutrition

You'll be running for 5+ hours. Your body can only store about 90 minutes of glycogen. You must eat and drink throughout the race.

Timing	What to Consume	Examples
Every 30–45 min	30–60g carbs	Gels, sweets, flapjack, sandwiches, bananas
Every 15–20 min	150–250ml fluid	Water, electrolyte drink
At aid stations	Real food if stomach tolerates it	Crisps, soup, boiled potatoes, cola (yes, really)

The Golden Rules of Ultra Nutrition

Rule	Why
Eat before you're hungry	By the time you feel hungry, you're already behind
Drink before you're thirsty	Same principle — stay ahead of dehydration
Practice everything in training	Your stomach needs training just like your legs
Have a backup plan	If gels stop working, switch to real food
Caffeine is your friend	Cola or caffeine gels in the second half can be a lifesaver

Essential Ultra Gear

Gear	Notes
Trail shoes	Most ultras are on trails. Grip and comfort over speed
Hydration vest/pack	Carry your own water and supplies between aid stations
Headtorch	Essential for 50-mile+ races or winter events
Waterproof jacket	Mandatory kit for most UK ultras
Blister kit	Compeed, tape, Vaseline — blisters are inevitable
Change of socks	Dry socks at halfway feel like a luxury spa treatment
GPS watch	Track distance and pace (but mostly ignore pace in an ultra)
Anti-chafe cream	Vaseline or specialist products on inner thighs, underarms, feet

Race Day Strategy

Pacing

Phase	Strategy
First third (0–17 km)	Deliberately easy. You should feel like you're holding back
Middle third (17–34 km)	Steady, comfortable effort. Eat and drink consistently
Final third (34–50 km)	Dig in. Walk the hills. Run the flats. Push to the finish

Walking Strategy

Walking is not a sign of weakness in an ultra. It's a strategy.

When to Walk	Why
Steep uphills	Power hiking is faster and more efficient than struggling to run
Aid stations	Walk through them, eat, drink, reset
When you need to eat	Eating while running at ultra pace often causes stomach issues
When your body demands it	Brief walk breaks preserve your legs for later

The Mental Game

Low Point	How to Handle It
"I can't do this"	Yes you can. This feeling will pass. Keep moving
Nausea	Slow down, sip water, eat something bland (plain crisps work well)
Wanting to quit at an aid station	Leave the aid station. You can always quit at the next one (you won't)
Pain	Assess: is it injury (stop) or discomfort (push through)?
Boredom	Talk to other runners. Listen to music. Count steps

What's Next?

Ready for the ultra world:

Plan your season with Periodisation & Annual Training Plan
Master your mind with Mental Toughness & Race Strategy
Track your training with Running with Data

Ultra Marathon Introduction🔒

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