Your First 50K: The Complete Kit List

A 50K needs three things a 10K does not: a way to carry water and food for hours, the mandatory safety kit your race lists in its rules, and a plan for feet and skin over a day that may run past eight hours. Everything here is either required by a race director or fixes a problem that appears after four hours, and the only dangerous item in an ultra is one you have not used before.

Read your race's mandatory kit list the day you enter, not the week before. Lists vary by race and season, and directors change them when the forecast turns.

Shoes, socks and skin

Race the shoe you have done your longest training days in. A 50K rewards late-run comfort over weight, so most people want more cushioning than they would pick for a 10K, and enough protection that hour six on rock is bearable. Size up if you are between sizes: a shoe that fits at the start can be too small once your feet swell.

Do not start an ultra in shoes near the end of their life. Midsoles go flat before outsoles look worn, so judge by the when to replace guidance, not the tread.

A spare pair in the drop bag

If the race allows a drop bag, put a second pair of shoes and dry socks in it. You may never touch them, but on a wet course, changing into dry shoes at halfway is the best stop you can make, because macerated skin blisters far more easily. Use the model you are racing in.

Socks are not the place to save money. Merino keeps structure and warmth soaked; cheap synthetic turns into sandpaper. Carry a spare pair in the vest.

Skin is the same idea. Balm on thighs, underarms, waistband, bra line and under any strap, before the start and again at an aid station, plus tape or plasters. Fixing a hotspot at 20 km costs two minutes; ignoring it costs the last 15 km.

The vest

The vest decides whether a 50K feels manageable, and capacity is set by the kit list, not the distance. A summer race with frequent aid fits in 5 or 6 litres; anything demanding a waterproof, two lamps and warm layers wants 8 to 12.

Fit matters more than capacity. Load it with everything you will carry, then run downhill: if it bounces, it will chafe. Prioritise front pockets you can reach on the move, since a vest you must stop to open is one you will underfuel with.

More in how to choose a running vest and best vests for 50K.

Hydration and electrolytes

Two 500 ml flasks is the standard setup and covers most aid station spacing. As a rule of thumb, plan on roughly 500 ml an hour in mild weather and more in heat, then check the profile: a long climb between stations means you leave full whatever the plan says. A bladder earns its place only when stations are far apart, since you cannot see what is left.

Electrolytes matter over a long hot day, and the approach is simple: get sodium from something consistent, whether tablets, sports drink or salty food. Keep one flask plain so you can wash a gel down. Flasks are consumables: pack a spare if you have had a bite valve fail.

Fuelling: how much to carry

The usual rule of thumb is 200 to 300 calories an hour. Most people need less than they feared early and more than they expected after five hours. Estimate your hours, multiply, then carry the gaps between stations plus a spare hour. Late-race stomachs get fussy, so variety is protection: gels, chews, a bar, something savoury for when sweet fails.

Aid station food is a bonus, not a plan: tables run out, and what is left may be nothing you have trained on.

Mandatory kit and weather layers

Check your race's rules, but expect this core list.

• Waterproof jacket, often with taped seams and a hood specified. Buy one that meets the rule; kit checks are common.
• Headlamp plus a spare if any of the field will be out after dark. Charge both beforehand.
• Foil blanket or bivvy, whistle, and a charged phone with race numbers saved.
• Collapsible cup. Cupless races are the norm, and without one you get no drink.
• Warm layer, light insulation or fleece, plus hat and gloves in season.

The primary lamp is worth spending on: enough output to descend at speed. The spare only has to get you off the hill.

Layers are about weather swings, not average temperature. A dawn start, an exposed ridge and a slow cold final hour can all happen in one race, and wind at hiking pace bites in a way it does not when you are running. Arm sleeves and a buff adjust without stopping. More in the headlamp guide.

Poles and drop bags

Poles earn their weight on sustained steep climbing, roughly 1,000 metres of gain and up, or if you fade on hills. They spread the work and steady tired descents, but they are dead weight on rolling ground and some races ban them. Practise for weeks: poling a climb is a skill.

Pack the drop bag for the version of you who arrives cold, tired and slightly stupid. Short list, labelled, food on top: dry socks, spare shoes, a fresh top, lube, a charged lamp for a night finish, and a food resupply.

The complete checklist

Category	Item	Mandatory in most races	Notes
Feet	Trail shoes, broken in, sized for swelling	No	Not a pair near the end of life
Feet	Merino socks	No	Spare pair in the vest
Feet	Spare shoes and socks in drop bag	No	Best item in the bag on a wet day
Carrying	Vest, 8 to 12 litres	Effectively yes	Size to the kit list, not distance
Hydration	2 x 500 ml soft flasks	Often, as a minimum volume	Some races specify 1 litre
Hydration	Electrolyte tablets	No	Keep one flask plain
Hydration	Collapsible cup	Yes	No cup, no drink
Fuel	Gels, chews, bar, savoury	Sometimes a minimum	Gaps plus one spare hour
Safety	Waterproof jacket, taped seams	Yes	Check the spec
Safety	Headlamp	Yes if dark is possible	Output to descend on
Safety	Spare lamp or batteries	Yes on night-capable races	Just has to get you off the hill
Safety	Foil blanket or bivvy	Yes	Weighs nothing, never omit it
Safety	Whistle	Yes	Often built into the sternum strap
Safety	Phone, charged, numbers saved	Yes	Flight mode saves battery
Safety	First aid bits and medication	Often	Plasters, tape, anything you need
Layers	Warm top, fleece or insulation	Often	For swings, not averages
Layers	Hat and gloves	Often, seasonal	Tiny, and they save a cold hour
Skin	Anti-chafe balm and spare	No	Before the start, again at halfway
Skin	Tape or blister plasters	No	Two minutes beats 15 km limping
Skin	Sunscreen and lip balm	Sometimes	Exposed courses
Extras	Poles	No	Sustained climbs only
Extras	GPS watch, course loaded	No	Never a substitute for markings

Common mistakes

Racing in anything new. New shoes, new vest, an untried gel: each is a coin flip you did not have to take.

Buying the vest last. Fit takes several loaded runs to dial in, and a vest that chafes at hour five cannot be fixed.

Treating the mandatory list as bureaucracy. It exists because someone got cold and stopped moving. Carry the real jacket, not the lightest thing that passes.

Underfuelling early. Nobody blows up at 40 km because of what they ate at 38 km. Start eating in the first hour.

Questions people ask

Do I really need a 12 litre vest?

Only if your race demands the full list. Lay the kit out and pack it into whatever vest you can borrow. If it fits with room to spare, you are fine. If you are cramming, buy bigger: a stuffed pack rides badly.

Can I use my 10K shoes?

If they are trail shoes with decent cushioning and you have run long in them, yes. What catches people out is protection: a low-stack shoe that feels great for an hour can leave your feet beaten up after six.

When should I have all of this ready?

Weeks out, not days. Every item wants a long run, and your biggest training day should be a dress rehearsal: same vest, same food, same shoes, same socks. That is where you find the strap that rubs and the gel that does not sit well, while it costs you nothing.