The UTMB® is not just a long race. It is a true ultra-trail where you may go from hot to cold, dry conditions to rain, day to night, and runnable terrain to highly technical sections. Your outfit must therefore be designed as a complete system.
Dressing properly for the UTMB® means finding the right balance between protection, breathability, comfort, weight, access to your gear, and your ability to adapt when conditions change. The goal is not to bring “as much as possible,” but to choose reliable, tested pieces that are easy to use and suited to your race pace.
This guide helps you structure your overall UTMB® equipment: base layer, waterproof jacket, trousers, pack, headlamp, poles, hydration, nutrition, and gear organization.
UTMB®: why your outfit should be designed as a system
In the UTMB®, you do not dress for a single type of weather. You equip yourself for an ultra in the mountains, with temperature changes, sections at night, slow climbs, technical descents, and possible stops at aid stations.
An effective outfit must meet three needs: let you run comfortably, protect you when conditions deteriorate, and remain easy to manage when you are tired. This is where the layering system becomes important.
Your base layer should remain breathable, comfortable, and stable with a hydration pack.
Your jacket, trousers, warm layer, and accessories should help you manage rain, wind, cold, and waiting.
Your gear must be easy to take out, put on, stow, and find again when fatigue sets in.
The base layer: the foundation of your comfort
Your base layer is what you wear for most of the race. It should be breathable, minimize chafing, and remain comfortable with a pack. In an ultra like the UTMB®, textile comfort becomes a real concern: a shirt that rubs, shorts that shift, or fabric that retains moisture can become very uncomfortable after several hours.
Your top: breathability, quick drying, and comfort under your pack
For your top, choose a technical shirt that efficiently wicks moisture, dries quickly, and remains comfortable under your pack straps. The seams, shoulder fit, and ability to ventilate matter more than weight alone.
If you run for a long time with a hydration vest, avoid choosing solely the lightest jersey. Also look at the contact zones, seams and stability under the pack.
A complete jersey for long efforts, designed for comfort, breathability and versatility thanks to the half-zip.
An ultra-lightweight, breathable jersey, ideal for hot sections or runners looking for an especially light feel.
Bottoms: shorts, compression shorts or 2-in-1?
For the UTMB®, the choice of bottoms depends mainly on your habits, but also on your tolerance for chafing and your preferred level of support to stay comfortable for hours. 2-in-1 shorts can be a good compromise: the freedom of shorts, the support of integrated compression shorts and accessible storage, depending on the model.
If you are prone to chafing between the thighs, compression shorts or 2-in-1 shorts are often more secure than classic shorts. The key is to test the model on a long run, with sweat, a pack and elevation gain.
Shorts with integrated compression shorts and a storage waistband, useful if you want to combine support, freedom of movement and quick access to small essentials.
Lightweight, breathable compression shorts for greater stability and reduced fabric movement over long periods.
The waterproof trail jacket: a piece not to overlook
The waterproof jacket is one of the most important pieces of your UTMB® gear. It must protect you from rain and wind while remaining breathable enough to prevent too much moisture from building up inside during exertion.
For a mountain ultramarathon, focus above all on the balance between waterproofing, breathability, weight, packability, hood, ease of putting it on, and compatibility with your pack.
An ultralight, compact jacket with an MP+® 25K / 50K membrane. Its gusset, compatible with packs up to 12 L, allows you to put it on over the vest without completely reorganizing your gear when the weather changes.
Ideal if you’re looking for a lightweight, highly breathable jacket.
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Waterproof trousers: essential mountain safety
Waterproof trousers may seem secondary as long as the weather is good. But during a long mountain race, they become important as soon as rain, wind, cold, or a long period of walking sets in.
The right trousers should stay compact, be easy to put on, and provide sufficient protection. One practical point to check: can you put them on quickly without taking off your shoes? During an ultramarathon, this detail can really matter.
Ultra-compact waterproof trousers designed to stay in your pack and be used when conditions deteriorate. Their main benefit: providing additional protection without unnecessarily weighing down your gear.
The trail running pack: organize your gear without being weighed down
On the UTMB®, your pack is your control center: water, nutrition, jacket, headlamp, battery, gloves, beanie, phone, emergency blanket, mandatory equipment, and accessories must be accessible at the right time.
The right choice depends on your level of self-sufficiency, how you organize your gear, and how much equipment you want to keep accessible without stopping. If it’s too small, the pack becomes difficult to organize. If it’s too large, you risk distributing the load poorly.
A minimalist choice for runners who want to stay light, with enough capacity if their gear is well optimized.
A more versatile pack if you want more storage, better organization and a more comfortable volume margin.
How should you organize your pack for UTMB®?
Organize your pack according to frequency of use. Items you use often should be accessible at the front: soft flasks, gels, bars, phone and small accessories. Items you use less often can go in the back: trousers, warm layer and emergency equipment.
Keep your jacket, headlamp and nighttime accessories in places that are easy to find. At night or in the rain, you do not want to empty your pack to look for an essential item.
The headlamp: see, be seen and stay alert
UTMB® involves running at night. Your headlamp should therefore be chosen carefully: power, battery life, comfort, stability, a spare battery and ease of use with gloves or cold hands.
On climbs, you can reduce the intensity to save battery power. On technical descents, increase the power to better read your foot placement and anticipate obstacles. Nighttime is mentally tiring: reliable lighting helps you stay focused.
A powerful headlamp for nighttime sections, technical descents and moments when terrain visibility becomes essential. This new model features a light that complies with UTMB® recommendations.
3h30 to 30h30 of battery life depending on the mode used.
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Poles: useful if you know how to use and carry them
In an ultra, poles are almost essential when they are permitted, as is the case at UTMB®. They will help you considerably, particularly on long climbs and technical descents. They help distribute effort, relieve the legs and improve stability. But they require proper learning.
If you set out with poles, train with them. Practise alternating push, simultaneous push, storage and transitions. On race day, your movement should be automatic.
A compact, lightweight pole, suitable for long-distance trails with alternating running sections and climbs using poles.
A practical solution if you often alternate between holding your poles and storing them, without wanting to take off your pack at every transition.
Hydration and nutrition: keep your energy up without overloading
At the UTMB®, hydration and nutrition need to be regular, accessible and tested. You should be able to drink often, eat without stopping for too long and vary the formats to avoid getting tired of them.
Organization is just as important as the products. Prepare your pockets in advance, separate your supplies into portions, and keep a simple reserve for moments when you no longer feel like having something sweet or when your stomach becomes more sensitive.
Accessible soft flasks, plain water, electrolytes or an energy drink depending on the heat, duration and your tolerance.
Alternate gels, bars, drinks, aid stations and foods you know you can digest after several hours.
Organize into blocks: what you eat now, what you save for later, and what you keep as a backup.
Accessories not to overlook
Small accessories may seem secondary, but over a race this long, they often make all the difference. Gloves, a beanie, neck gaiter, cap, sunglasses, suitable socks, anti-chafing cream or plasters can help you avoid suffering through the race.
The goal is not to carry too much, but to have the right essentials to handle changing weather, long descents, darkness, sun, chafing and rest stops.
Cap or headband, beanie depending on the conditions, neck gaiter for cool or windy sections.
Gloves suited to the weather and usable with your poles, headlamp, and phone.
Socks tested over long distances, blister management, and a spare pair if your race organization allows it.
Sunglasses, a cap, sun protection, and breathable clothing for exposed sections.
General checklist for what to wear at the UTMB®
This checklist does not replace the official mandatory equipment list, which should always be checked before the race. Instead, it helps you think of your equipment as a coherent whole.
| Category | Purpose | What to check |
|---|---|---|
| Technical running shirt | Breathability, quick drying, reduced chafing | Comfort under a pack and seams |
| Shorts, half tights, or 2-in-1 shorts | Staying comfortable over long periods | Chafing, support, pockets |
| Waterproof jacket | Protection from rain, wind, and cold | Waterproofing, breathability, packability |
| Waterproof trousers | Adding weather protection | Ease of putting on and weight |
| Trail running pack | Carrying gear, water, and nutrition | Volume, access, stability |
| Headlamp | Seeing, being seen, and staying clear-headed at night | Battery life, power, spare battery |
| Poles | Taking the strain off your legs and providing stability | Technical features, storage, carrying |
| Accessories | Managing cold, sun, chafing, and unexpected conditions | Easy access and testing during a long run |
In summary: what outfit should you choose for the UTMB®?
When dressing for the UTMB®, think in terms of a system first: a breathable base layer, reliable weather protection, a well-organized pack, a tested headlamp, accessible nutrition, and accessories suited to the mountains.
The right equipment isn’t the one that looks perfect on a product page. It’s the equipment you have tested in real-world conditions, know how to use quickly, and can stay comfortable in after several hours of effort.
Cold- or heat-weather kits require specific consideration. But to build your UTMB® essentials, focus on the basics: breathability, protection, accessibility, stability, and simplicity. The clearer and more manageable your equipment is, the more you can focus on your race.
