Gear Guide

Ultra Marathon Apparel & Running Clothing

Dress for comfort, performance, and survival across any distance and conditions.

The right apparel system isn't about brand loyalty — it's about matching fabric, weight, and layering to your specific race conditions. A poorly chosen shirt can end a 100-mile race through chafing alone. The wrong insulation layer can cause hypothermia on a mountain at 2am. Get this right.

The first rule of ultra apparel: cotton kills, synthetics and merino save.

Build Your Race Outfit

5 questions → a complete layering recommendation with specific products.

Outfit Finder

5 questions → a complete outfit recommendation for your race.

Question 1 of 5

What's your race distance?

Base Layers — Tops

Base Layers — Tops

Your first line of defense against sweat, sun, and cold

The shirt touching your skin determines everything: blister prevention at the underarms, temperature regulation, and whether you smell like a human being at mile 80. Cotton is never the answer.

Patagonia

Patagonia

Capilene Cool Daily Shirt

$453.7 oz

Material: Recycled polyester with Polygiene treatment

Fit: Men's & Women's

Best for

Hot weather ultrasDesert racingHigh UV exposure

Pros

  • +UPF 50+ sun protection built into fabric
  • +Polygiene odor control — stays fresh for days
  • +Ultralight and fast-drying

Cons

  • Not warm enough for cool mornings
  • Synthetic odor can build over multiple long runs
  • Plain aesthetic

Salomon

Salomon

Sense Aero Tee

$503.5 oz

Material: 37.5 technology polyester

Fit: Men's & Women's

Best for

Technical trail racingHot to moderate conditionsRunners wanting performance fit

Pros

  • +37.5 technology actively moves moisture at a cellular level
  • +Seamless construction eliminates underarm chafe points
  • +Motion-fit design moves with you on technical terrain

Cons

  • Salomon sizing runs European/slim — size up
  • Limited color options
  • Higher price for a single technical tee

Smartwool

Smartwool

Merino 150 Short Sleeve

$754.2 oz

Material: Merino wool blend

Fit: Men's & Women's

Best for

Multi-day racingTemperature-variable conditionsOdor-sensitive runners

Pros

  • +Wearable for multiple days without washing — odor resistance is real
  • +Natural temperature regulation works both ways (cool in heat, warm when cool)
  • +Naturally moisture-wicking without synthetic chemicals

Cons

  • More expensive than synthetic options
  • Slower to dry than polyester
  • Requires more careful washing

Smartwool

Smartwool

Merino 250 Base Layer Crew

$1006.0 oz

Material: 100% Merino wool

Fit: Men's & Women's

Best for

Cold weather ultrasNight sectionsSub-freezing temperatures

Pros

  • +Heavyweight merino provides real insulating warmth
  • +Breathes during exertion — doesn't trap heat like synthetics
  • +Odor-resistant for multi-day events

Cons

  • Too warm for anything above 50°F at race pace
  • Premium price point
  • Requires careful washing

Outdoor Research

Outdoor Research

Echo Long Sleeve

$553.8 oz

Material: Recycled polyester

Fit: Men's & Women's

Best for

Sun protection on exposed terrainCool morning startsBudget-conscious runners

Pros

  • +Thumbholes keep sleeves down on long descents
  • +Best value long-sleeve performance shirt available
  • +UPF 30+ sun protection

Cons

  • Not as technical as Salomon or Patagonia options
  • Average odor control
  • Somewhat loose fit
Shorts & Bottoms

Shorts & Bottoms

Chafe prevention and pocket access define your race

The wrong shorts will sideline you with chafing by mile 30. The right ones carry your nutrition, stay in place, and feel like nothing after 100 miles. Liner, pocket count, and inseam are everything.

Patagonia

Patagonia

Strider Pro Shorts 5"

$652.8 oz

Material: Recycled nylon ripstop

Fit: Men's & Women's

Best for

Versatile distance racingHot to moderate conditionsMinimalist runners

Pros

  • +DWR finish handles light rain and stream crossings
  • +Built-in liner eliminates need for separate underwear
  • +Secure back pocket fits gels and phone

Cons

  • Only 2 pockets — not enough for 100-mile nutrition needs
  • Thin liner isn't for everyone
  • Limited color options

Janji

Janji

5" AFO Middle Short

$683.1 oz

Material: 4-way stretch performance fabric

Fit: Men's & Women's

Best for

Long distance racingNutrition-heavy runnersRunners who need pockets

Pros

  • +6 total pockets — enough to carry a full race-day nutrition plan
  • +Split hem gives unrestricted stride on technical terrain
  • +Performance liner is genuinely comfortable over 100 miles

Cons

  • Higher price for shorts
  • Pocket weight can feel unbalanced when fully loaded
  • Limited inseam options

Patagonia

Patagonia

Nine Trails 8" Short

$754.2 oz

Material: Recycled polyester/nylon blend

Fit: Men's & Women's

Best for

Technical terrainModest coverage preferenceMixed trail/scrambling

Pros

  • +DWR coating handles brush and light rain
  • +8" inseam prevents inner thigh chafing
  • +Multiple pockets including secure back zip

Cons

  • Heavier than racing-specific shorts
  • Not ideal for speed-focused runners
  • 8" can feel warm in peak heat

Patagonia

Patagonia

Capilene Midweight Tights

$895.5 oz

Material: Recycled polyester

Fit: Men's & Women's

Best for

Cold weather racingNight sectionsBelow-50°F conditions

Pros

  • +Moisture-wicking insulating fabric for cold weather base layer
  • +Flatlock seams prevent chafing over long efforts
  • +Comfortable waistband doesn't dig over 20+ hours

Cons

  • Not warm enough for extreme cold without layering
  • No pockets
  • Can feel restrictive at faster paces

Salomon

Salomon

Trail Runner Wind Tight

$1105.8 oz

Material: Weather Shield polyester

Fit: Men's & Women's

Best for

Cold/windy mountain racingTechnical alpine terrainRunners who prioritize leg protection

Pros

  • +Wind-resistant — noticeable difference on exposed ridgelines
  • +Reflective details for night visibility
  • +Storage pockets on thigh and back

Cons

  • Premium price for tights
  • Not as breathable as non-windproof options
  • Salomon sizing runs slim
Insulation & Mid Layers

Insulation & Mid Layers

Packable warmth that earns its space in your vest

Every layer in your vest costs you space and weight. Insulation needs to earn its place by being compressible, light, and warm when you stop moving. These do all three.

Patagonia

Patagonia

Nano Puff Jacket

$24912.6 oz

Material: PrimaLoft Gold insulation

Fit: Men's & Women's

Best for

Aid station warmthCold mountain conditionsPackable mid/outer layer

Pros

  • +PrimaLoft insulates when wet — critical for rain and sweat in cold races
  • +Packs into its own pocket — compresses small enough for any running vest
  • +Weather-resistant shell keeps wind and light rain out

Cons

  • Premium price
  • Synthetic not as warm-to-weight as high-fill down
  • Gets warm quickly when running hard

Arc'teryx

Arc'teryx

Atom LT Hoody

$27910.6 oz

Material: Coreloft Compact 60g insulation

Fit: Men's & Women's

Best for

Active mountain useBelay-style warmth for aid stationsAlpine racing

Pros

  • +Breathable Tyono panels prevent overheating at pace
  • +Helmet-compatible hood works over running hats and headlamps
  • +Arc'teryx construction quality is industry-leading

Cons

  • Most expensive option in this category
  • Less packable than Nano Puff
  • Not available in as many colors

Mountain Hardwear

Mountain Hardwear

Ghost Whisperer/2

$3807.0 oz

Material: 800-fill responsibly sourced down

Fit: Men's & Women's

Best for

Ultralight 100-mile packersDry cold conditionsWeight-obsessed runners

Pros

  • +7 oz is the lightest warm jacket in this guide — genuinely remarkable
  • +800-fill down is the warmth-to-weight benchmark
  • +Compresses to fist-sized — uses essentially zero vest space

Cons

  • Loses insulation value when wet — risky in rain-prone races
  • Premium price for a single jacket
  • Delicate fabric tears easily

Patagonia

Patagonia

R1 Hoody

$14910.5 oz

Material: Polartec Power Stretch grid fleece

Fit: Men's & Women's

Best for

Active mid-layer useHigh-exertion cold weatherBreathable warmth during running

Pros

  • +Most breathable insulation layer available — designed for active use
  • +Grid fleece interior wicks moisture away from base layer
  • +Hood adds versatility without excessive bulk

Cons

  • Not designed to stop wind or rain — needs a shell over it
  • Less packable than insulated jackets
  • Limited warmth in extreme cold
Rain & Wind Shells

Rain & Wind Shells

Mandatory gear that must perform when conditions turn

Many races mandate a waterproof jacket. Even when they don't, a shell is non-negotiable for 100-mile mountain races. Weight and packability determine whether runners actually carry it vs. leave it at camp.

Outdoor Research

Outdoor Research

Helium Rain Jacket

$1506.4 oz

Material: Pertex Shield waterproof membrane

Fit: Men's & Women's

Best for

Budget-conscious waterproof protectionMost ultra running conditionsRace mandatory gear

Pros

  • +6.4oz is genuinely ultralight at this price point
  • +Packs into its own chest pocket — attached stuff sack
  • +Meets most race mandatory gear requirements

Cons

  • Less breathable than Gore-Tex alternatives
  • Durability lower than premium options
  • Limited feature set

Patagonia

Patagonia

Storm Racer Jacket

$1998.0 oz

Material: H2No 2.5-layer waterproof membrane

Fit: Men's & Women's

Best for

Trail-running specific protectionBreathable waterproofingAll-conditions racing

Pros

  • +H2No membrane balances waterproofing and breathability better than most
  • +Trail-running cut — helmet hood, motion-fit arms
  • +Adjustable hem and hood without stopping

Cons

  • More expensive than Helium
  • Some find H2No less breathable than eVent
  • Hood can obstruct peripheral vision

Arc'teryx

Arc'teryx

Norvan SL Hoody

$2994.7 oz

Material: Gore-Tex Shakedry

Fit: Men's & Women's

Best for

Ultralight 100-mile mountain racingUTMB-style mandatory gearElite runners every gram counts

Pros

  • +4.7oz — lightest waterproof shell in trail running
  • +Gore-Tex Shakedry never wets out — water rolls off instantly
  • +Rolls into its own hood — takes almost no vest space

Cons

  • $299 is a serious investment for a jacket
  • Shakedry fabric is delicate — not for bushwhacking
  • No chest pockets

Salomon

Salomon

Bonatti WP Jacket

$1308.5 oz

Material: AdvancedSkin Dry waterproof membrane

Fit: Men's & Women's

Best for

Value waterproof protectionRace mandatory gearTraining conditions

Pros

  • +Most affordable waterproof jacket that genuinely works
  • +Motion Fit construction allows full arm movement
  • +Packs into side pocket for easy access

Cons

  • AdvancedSkin Dry less breathable than Gore-Tex
  • Heavier than ultralight options
  • Salomon sizing runs slim

Patagonia

Patagonia

Houdini Jacket

$1193.8 oz

Material: Nylon ripstop with DWR

Fit: Men's & Women's

Best for

Wind protectionLight shower coverageVest-pocket emergency layer

Pros

  • +3.8oz packs into its own chest pocket
  • +The definitive packable wind shell
  • +DWR handles light rain for 20–30 minutes

Cons

  • Not a true waterproof jacket — won't survive sustained rain
  • Best paired with waterproof shell in the vest
  • DWR wears off and requires reapplication
Socks

Socks

The most important piece of apparel per dollar spent

Blisters end more races than bonking. The right socks, sized correctly and worn with race shoes, are the difference between walking mile 70 and running it. Never scrimp here.

Darn Tough

Darn Tough

Run No-Show Tab Lightweight

$22/pair

Material: Merino wool + nylon

Fit: Men's & Women's

Best for

All-distance ultra runningBlister-prone runnersHot to moderate conditions

Pros

  • +Lifetime warranty — Darn Tough replaces any sock that wears out, ever
  • +Merino wool manages moisture and odor naturally
  • +Seamless toe construction eliminates the #1 blister cause

Cons

  • Premium price for socks
  • Takes a few washes to fully break in
  • Merino less durable than pure synthetics over many years

Feetures

Feetures

Elite Max Cushion No Show

$16/pair

Material: Nylon + spandex

Fit: Men's & Women's

Best for

Maximum cushioningLong distance comfortRunners with sensitive feet

Pros

  • +Anatomical left/right design — genuinely fits better than ambidextrous socks
  • +Targeted compression in arch and heel prevents slippage
  • +Lifetime guarantee from Feetures

Cons

  • Synthetic-only — less odor-resistant than merino options
  • Max cushion can feel too warm in heat
  • No tab for Achilles protection

Balega

Balega

Hidden Comfort No Show

$14/pair

Material: Mohair + synthetic blend

Fit: Men's & Women's

Best for

Budget-conscious runnersPlush cushioning preferenceModerate conditions

Pros

  • +Best value sock in this guide — $14 with quality construction
  • +Deep heel pocket prevents sock slippage
  • +Hand-linked seamless toe is genuinely comfortable

Cons

  • No lifetime guarantee
  • Less blister-resistant than Darn Tough or Feetures
  • Mohair can pill over time

Injinji

Injinji

Run Lightweight No-Show Tab

$16/pair

Material: CoolMax + nylon

Fit: Men's & Women's

Best for

Toe-blister preventionWide toe box shoe usersRunners with toe issues

Pros

  • +Individual toe sleeves eliminate all toe-to-toe blister contact
  • +Perfect for wide toe box shoes (Altra, Topo)
  • +CoolMax manages moisture efficiently

Cons

  • Toe sleeves require time to put on (harder at mile 60 aid station)
  • Unusual feel requires adaptation period
  • Not for narrow-fit shoes

Smartwool

Smartwool

PhD Run Light Elite Micro

$22/pair

Material: Merino wool + nylon

Fit: Men's & Women's

Best for

All-conditions racingOdor-sensitive runners4-season versatility

Pros

  • +4 Degree fit system targets comfort across the foot
  • +Merino's natural temperature regulation works in both heat and cool
  • +Smartwool quality construction lasts multiple seasons

Cons

  • Premium price
  • Smartwool's warranty less comprehensive than Darn Tough
  • Merino slower to dry than synthetic options
Hats, Gloves & Accessories

Hats, Gloves & Accessories

Small items with outsized impact on comfort and safety

Accessories are where races are lost to cold hands, eye strain, and neck exposure. They weigh almost nothing in your vest but matter enormously when conditions change.

Salomon

Salomon

XA Cap

$30

Material: Lightweight mesh

Fit: Unisex

Best for

Hot weather racingSun protectionFast trail running

Pros

  • +Featherlight construction — barely know it's there
  • +UPF 30+ protection
  • +Moisture-wicking sweatband

Cons

  • Limited brim for serious sun protection
  • Less structured than some prefer
  • Not for cold weather

Ciele

Ciele

GOCap

$38

Material: COOLwick fabric

Fit: Unisex

Best for

Moderate conditionsRunners wanting premium running capsStyle-conscious athletes

Pros

  • +COOLwick technology actively manages sweat
  • +Technical running-specific cut
  • +Best overall running cap aesthetic

Cons

  • Higher price for a cap
  • Less ventilation than mesh alternatives
  • Limited brim

Smartwool

Smartwool

Merino 250 Beanie

$35

Material: Merino wool

Fit: Unisex

Best for

Cold weather racingNight runningMountain conditions

Pros

  • +Merino warmth without synthetic bulk
  • +Odor-resistant for multi-day events
  • +Fits under headlamp and hydration vest hoods

Cons

  • Too warm for moderate conditions
  • Slower drying than synthetic beanies
  • Can shift under headlamp

Buff

Buff

Original Multifunctional Headwear

$20

Material: Microfiber polyester

Fit: Unisex

Best for

Versatile year-round useSun/wind/dust protectionDrop bag essential

Pros

  • +12+ wearing configurations — beanie, neck gaiter, bandana, face mask
  • +Essential piece at $20 — buy three
  • +UPF 50+ in standard fabric

Cons

  • Minimal insulation in standard version
  • Can slip when worn as hat
  • Limited warmth in cold conditions (Merino version needed for cold)

Smartwool

Smartwool

Merino 150 Gloves

$40

Material: Merino wool + nylon

Fit: Unisex

Best for

Cool to cold runningNight sectionsTouchscreen use while running

Pros

  • +Touchscreen compatible — operate your watch without removing gloves
  • +Merino regulates temperature — comfortable from 25–50°F at running pace
  • +Odor-resistant for multi-day events

Cons

  • Not warm enough for extreme cold (below 20°F) without overmitts
  • Merino wears faster than synthetic gloves
  • No wind protection

Goodr

Goodr

Goodr Running Sunglasses

$25

Material: Lightweight frames, polarized lens

Fit: Unisex

Best for

Budget-conscious runnersAll-day racingFun aesthetic

Pros

  • +No-bounce design engineered specifically for running
  • +Polarized at $25 — unmatched value
  • +Dozens of fun color options

Cons

  • Less durable than Oakley or Tifosi
  • Limited field of view vs. wrap-around styles
  • Not ideal for truly technical terrain where full protection matters

Oakley

Oakley

Radar EV Path

$193

Material: O-Matter frame, Prizm lens

Fit: Unisex

Best for

Premium opticsVariable light conditionsLong exposure racing

Pros

  • +Prizm lens technology optimizes contrast for trail surfaces
  • +Large lens provides maximum field of view for trail obstacles
  • +Secure fit stays put during technical running

Cons

  • Most expensive sunglasses in this guide
  • Can fog in humid conditions
  • Premium target for theft at aid stations

Salomon

Salomon

Trail Gaiters Low

$25

Material: Breathable nylon

Fit: Unisex

Best for

Debris preventionSandy/rocky terrainShoe-gaiter system users

Pros

  • +Keeps rocks, sand, and pine needles out of shoes
  • +Compatible with Salomon shoe attachment system
  • +Breathable — you won't notice them after mile 1

Cons

  • Requires compatible shoes (attachment tabs)
  • Low-cut doesn't help with deep mud
  • Extra step in race prep
Anti-Chafe & Undergarments

Anti-Chafe & Undergarments

The unsexy products that save your race

Chafing is entirely preventable and absolutely race-ending. Apply before you start, reapply at crew stops, and carry it in your vest. These products cost pennies per mile of comfort.

Body Glide

Body Glide

Original Anti-Chafe Balm

$9

Material: Plant-derived, non-greasy

Fit: Unisex

Best for

Pre-race applicationKnown chafe pointsAll conditions

Pros

  • +The industry standard — used by more ultra runners than any other anti-chafe
  • +Non-greasy stick applicator is fast and clean
  • +Plant-based formula safe for sensitive skin

Cons

  • Needs reapplication at 50M+ for some runners
  • Stick format can be awkward for inner thighs
  • Can transfer to clothing

Squirrel's

Squirrel's

Nut Butter

$14

Material: All-natural oils and butters

Fit: Unisex

Best for

Heavy sweaters100-mile effortsSensitive skin runners

Pros

  • +All-natural ingredients — no synthetic chemicals on skin for 30 hours
  • +Cream formula covers large areas faster than sticks
  • +Superior waterproofing — stays on through 10+ hours of sweating

Cons

  • More expensive than Body Glide
  • Cream can feel greasy initially
  • Packaging less convenient than a stick

2Toms

2Toms

SportShield Roll-On

$15

Material: Silicone-based formula

Fit: Unisex

Best for

Roll-on convenienceFull-body coverageLong-lasting protection

Pros

  • +Roll-on applicator reaches everywhere — especially the back
  • +Silicone base is extremely durable and water-resistant
  • +No residue on clothing

Cons

  • Silicone-based — some prefer natural alternatives
  • Roll-on can take longer than stick to apply
  • Less widely available than Body Glide

ExOfficio

ExOfficio

Give-N-Go Boxer Brief

$28

Material: Nylon/elastane blend

Fit: Men's

Best for

Under shorts useMulti-day racingSensitive chafe areas

Pros

  • +Quick-dry nylon dries within hours even without removing
  • +Antimicrobial treatment prevents bacterial chafing
  • +Ultra-favorite for 100-mile events with shorts that have thin liners

Cons

  • Extra layer adds warmth in heat
  • Not necessary with shorts that have good liners
  • Needs washing after every use

Layering by Conditions

The layering system that keeps you comfortable from a summer desert 50K to a winter mountain 100-miler.

Hot (75°F+)

~$165 estimated

Top: Patagonia Capilene Cool DailyUPF 50+, Polygiene
Bottom: Janji 5" AFO ShortPockets, 4-way stretch
Socks: Darn Tough No-Show LowMerino, lifetime warranty
Head: Salomon XA CapUPF, mesh vent
Eyes: Goodr Running SunglassesNo-bounce, polarized

Start with ice in your hat and bandana. Apply sunscreen AND SPF lip balm.

Moderate (50–75°F)

~$320 estimated

Top: OR Echo Long SleeveSun protection, thumbholes
Bottom: Patagonia Strider Pro 5"DWR, built-in brief
Socks: Balega Hidden ComfortPlush, seamless toe
Head: Ciele GOCapCOOLwick, technical
Vest pocket: Patagonia HoudiniWind/light rain

Moderate days change — morning cold, afternoon warm. Layer for the start, not the peak.

Cool (35–50°F)

~$380 estimated

Base Top: Smartwool Merino 150 LSNatural temp regulation
Base Bottom: Patagonia Capilene TightsInsulating base
Mid Layer: Patagonia Nano Puff VestCore warmth, packable
Head: Smartwool Merino 250 BeanieMerino, under headlamp
Hands: Smartwool Merino 150 GlovesTouchscreen, lightweight

The vest goes in your pack when you warm up — arms free, core warm.

Cold (20–35°F)

~$500 estimated

Base Top: Smartwool Merino 250 CrewHeavyweight warmth
Base Bottom: Smartwool Merino 250 TightsFull warm base
Mid: Patagonia R1 HoodyBreathable active fleece
Shell: OR Helium Rain JacketWind/water barrier
Head + Hands: Full accessories kitBeanie + liner gloves + Buff

Your biggest cold-weather mistake: not having a dry base layer in your drop bag.

Wet / Rainy

~$350+ estimated

Base: Quick-dry synthetic (not merino)Dries faster when soaked
Shell: Patagonia Storm Racer JacketH2No waterproof
Bottom: DWR-treated shorts/tightsSheds water off thighs
Head: Patagonia Duckbill CapBrim keeps rain off face
Hands: Waterproof gloves or shellsWet = cold hands fast

Extra dry socks in your vest. Wet feet are inevitable — dry socks reset you.

Mountain / Alpine

~$600+ estimated

Base: Smartwool Merino 150 LSNatural temp buffer
Insulation: Patagonia Nano Puff JacketCompresses to fist-size
Shell: Arc'teryx Norvan SL HoodyLightest waterproof available
Accessories: Full cold weather kitBeanie, gloves, Buff
Night add-ons: Extra base, hand warmersTemps drop 30°F at night

Mountain races: all layers accessible in vest top pocket. Never dig for emergency gear.

Fabric Technology Guide

Know what you're buying. These are the technologies that actually matter over 100 miles.

Base Fabrics

Merino Wool

Temperature regulating, odor-resistant, naturally moisture-wicking. Slower to dry than synthetic. Best for multi-day events.

Polyester

Fast-drying, durable, affordable. Retains odor over time. Nike Dri-FIT, Patagonia Capilene.

Nylon

Softer feel than polyester, more durable, excellent moisture management. Patagonia's preferred synthetic.

Merino Blends

Best of both: wool odor resistance + synthetic durability and drying speed. Smartwool PhD line.

Insulation Tech

Down (800+ fill)

Best warmth-to-weight ratio. Loses insulation when wet. Best for dry cold. Mountain Hardwear Ghost Whisperer.

PrimaLoft / Coreloft

Synthetic insulation that works when wet. More durable than down. Patagonia Nano Puff, Arc'teryx Atom.

Polartec Fleece

Breathable active insulation. Grid interior wicks moisture. Best mid-layer for running. Patagonia R1.

37.5 Technology

Active particles in fiber move moisture and maintain optimal body temp. Salomon uses extensively.

Weather Membranes

Gore-Tex

Gold standard waterproof-breathable. Expensive, durable, widely trusted. Arc'teryx Beta LT.

Gore-Tex Shakedry

Exposed membrane — lightest waterproof available. Delicate but remarkable. Arc'teryx Norvan SL.

Patagonia H2No

Patagonia's proprietary membrane. Excellent breathability/waterproofing balance at lower price.

DWR Coating

Surface treatment that beads water. Not waterproof — needs shell behind it. Reapply with Nikwax periodically.

Sustainability

Bluesign Approved

Certification for safe, sustainable fabric production. Patagonia, Arc'teryx, Outdoor Research.

Recycled Content

Patagonia's Capilene uses 100% recycled polyester. Performance identical to virgin synthetic.

ZQ Merino

Ethical merino sourcing standard. Animal welfare + land management. Smartwool, Icebreaker.

Polygiene

Antimicrobial treatment that reduces wash frequency — less water, less energy. Patagonia, various brands.

Clothing by Race Distance

Longer races require more clothing redundancy, drop bag planning, and night-section preparation.

50K

4–10 hrs

$200–500

Race Day Outfit

  • Single full outfit (weather-appropriate)
  • 1 layering option in vest
  • Hat, sunglasses, buff

Drop Bags

  • ·No drop bags typically needed
  • ·Extra sock pair if long course

Test your exact race-day outfit on a 15-20 mile training run first.

50 Miles

7–14 hrs

$400–700

Race Day Outfit

  • Start outfit
  • 1-2 layering options in vest
  • Full accessories kit

Drop Bags

  • ·Extra shirt
  • ·1-2 extra sock pairs
  • ·Warmer layer if evening finish
  • ·Fresh hat

Plan for the temperature at your estimated finish time, not the start.

100K

10–20 hrs

$600–1,000

Race Day Outfit

  • Day start outfit
  • Night transition layer in vest
  • 2-3 layering options accessible

Drop Bags

  • ·Mid-race shirt change
  • ·2-3 sock pairs
  • ·Night running warm kit
  • ·Emergency dry base layer

Day-to-night transition is where most clothing mistakes happen. Plan it explicitly.

100 Miles

20–36 hrs

$800–1,500

Race Day Outfit

  • Multiple complete outfits
  • Full layering system at all times
  • Night gear must be accessible without stopping

Drop Bags

  • ·4-6 fresh sock pairs
  • ·3-4 fresh shirts
  • ·2 fresh shorts/tights
  • ·Full night kit in 50-mile bag
  • ·Rain gear at every bag

A fresh shirt and clean socks at mile 70 can save a race psychologically. Include them.

Clothing Care & Longevity

Proper care extends the life of technical apparel by years. These aren't regular clothes.

Washing Rules

  • Cold water always — heat degrades technical fabrics
  • Gentle cycle — tumble damages DWR and stretchy fibers
  • Sport-specific detergent (Nikwax Sport Wash, Sport Suds) — regular detergent clogs moisture-wicking
  • No fabric softener — ever — it destroys wicking properties
  • Turn garments inside out to reduce pilling
  • Zip all zippers before washing

Drying Rules

  • Air dry whenever possible — extends fabric life by years
  • No high heat in dryer — degrades elastic and synthetic fibers
  • Waterproof shells: tumble dry LOW to reactivate DWR coating
  • Down jackets: tumble dry LOW with tennis balls to restore loft
  • Merino wool: lay flat to dry — hanging stretches it
  • Out of direct sunlight — UV degrades many fabrics

DWR Maintenance

  • DWR (water-repellent coating) wears off with use and washing
  • Signs it's gone: jacket 'wets out' and feels heavy in rain
  • Restore by washing and tumble drying — heat reactivates DWR
  • If that fails: apply Nikwax TX.Direct or Granger's spray
  • Reapply every season or when performance drops
  • Never use regular detergent on waterproof shells

Merino Wool Care

  • Wash less frequently — merino can be worn 3-5 times before washing
  • Use wool-specific detergent (Eucalan, Nikwax Wool Wash)
  • Cool water only — warm water causes felting and shrinking
  • Lay flat to dry — never hang or machine dry
  • Pilling is normal — use a fabric shaver to remove
  • Never bleach — destroys wool fiber permanently

When to Replace

  • Fabric has thinned noticeably (hold to light — transparency test)
  • Holes or tears that can't be repaired with seam tape
  • Lost stretch — waistbands, cuffs that no longer grip
  • Persistent odor that washing can't remove (bacterial saturation)
  • Waterproofing can't be restored despite DWR reapplication
  • Seams failing in multiple places

Warranties to Know

  • Darn Tough: Unconditional lifetime warranty — replace any worn-out sock free
  • Patagonia: Ironclad Guarantee — repair, replace, or refund regardless of age
  • Arc'teryx: Lifetime limited warranty on manufacturing defects
  • Feetures: Lifetime guarantee on their performance socks
  • Smartwool: Limited lifetime guarantee on defects
  • Register your gear — warranties require proof of purchase

Frequently Asked Questions

What should I wear for my first ultra?
Start simple: a moisture-wicking shirt, running shorts with a liner, quality socks (Darn Tough or Balega), and a running cap. If the course requires a rain jacket, add an Outdoor Research Helium. The most important rule: wear the exact outfit on a 15–20 mile training run before race day. Never debut anything new on race day.
Cotton or synthetic? Is it really that important?
Yes — this is one of the few non-negotiable rules in ultra running. Cotton absorbs sweat and stays wet, causing chafing over long distances and dangerous heat loss in cold conditions. Wet cotton against skin in cold mountains can cause hypothermia. Synthetic fabrics (polyester, nylon) and merino wool wick moisture away and dry quickly. This isn't marketing — it's physics.
Is merino wool worth the extra cost?
For multi-day or 100-mile races, yes — particularly for socks and base layers. Merino's odor resistance means you can wear it for 24+ hours without the bacterial buildup that synthetics develop. Temperature regulation also works in both directions. For training and shorter races, quality synthetics like Patagonia Capilene perform similarly at lower cost.
How do I prevent chafing?
Four-part strategy: (1) Wear moisture-wicking technical fabrics everywhere — no cotton, no rough seams. (2) Apply Squirrel's Nut Butter or Body Glide to all known problem areas before the start (inner thighs, underarms, nipples, waistband line). (3) Reapply at crew access points — anti-chafe breaks down over time. (4) Carry a small amount of anti-chafe in your vest for emergency mid-race application.
Should I wear compression?
The evidence for compression during running is modest. Compression socks and tights may reduce muscle vibration and perceived fatigue, and there's clearer evidence for their recovery benefits post-race. Many ultra runners swear by calf sleeves on long efforts. If you've used compression in training without issues, feel free to race in it. Don't debut it on race day.
What do I wear at night?
Night brings two challenges: lower temperatures and visibility. Temperature: add at least one layer even if the day was warm — desert temperatures drop 30–40°F at night, and mountains are colder still. Plan a night layer in your vest. Visibility: choose clothing with reflective elements, wear your headlamp, and consider a blinking light on your vest back. Gloves and a hat belong in every night section kit.
How many pairs of socks should I bring?
More than you think. For a 50K: 1 spare pair in your vest. For a 50M: 2 pairs (one per major drop bag). For a 100K: 3 pairs. For a 100M: 4–6 pairs minimum, including waterproof trail crossings. Fresh socks at mile 70 of a hundred can literally save your race — the psychological lift of clean, dry socks is real and documented.
When should I change clothes during a 100-miler?
At minimum: fresh socks and a dry shirt at your mile 50–60 drop bag before the night section. Ideally: fresh everything at each major drop bag opportunity. Wet, dirty clothing causes chafing that compounds over hours. A clean kit isn't a luxury in a 100-miler — it's maintenance. Your body will thank you at mile 80.
Can I wear the same outfit for training and racing?
Yes — and you should. Race-day clothes should be your most-tested training clothes. The worst strategy is buying special race-day gear and wearing it for the first time at mile 1. Your training outfit IS your race outfit. If you want to invest in higher-quality race-specific pieces (lighter, more pockets), break them in for 50+ miles in training first.
How do I dress for variable mountain weather?
The alpine layering principle: always carry more than you need, compressed as small as possible. A mountain race can go from 70°F sun to 40°F rain to 25°F wind in a single day. Your vest should always contain: a windproof layer, waterproof shell, warm hat, and gloves — even if you start in shorts and a t-shirt. Mountain weather is non-negotiable.

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