Skills
Almost every hiking blister warns you first, as a warm, rubbing patch called a hot spot. Stop for five minutes when you feel one and the rest of the day stays good. Below: what causes blisters, how to set your feet up before the trailhead, and what to do when one starts anyway.
A hiking blister almost always gives you a warning first: a warm, rubbing patch on a heel or a toe, the spot hikers call a hot spot. Stop then, take the boot off and cover it, and the blister usually never forms. Push on to the next viewpoint and you can end up limping the last five miles.
That warning window makes blisters very preventable, yet they're still the most common medical complaint on long trails. In a survey of 280 Appalachian Trail backpackers, 64 percent reported foot blisters, more than reported diarrhea or joint pain. Toughing it out doesn't help. Fit, dry feet, the right tape in the right place and stopping early do.
Treat foot care as part of planning the day, like checking the weather. The sections below cover how a blister actually forms, the causes worth fixing at home, and a five-minute routine for the trail.
1997 survey of 280 hikers
Randomized trial, multistage ultramarathons
American Academy of Dermatology
A friction blister forms when something rubs the skin back and forth until its layers start to separate. Fluid seeps into the gap and lifts the outer skin into a bubble. It happens in stages, and each stage has its own fix.
Stage 1
Your sock and boot move against your skin with every step. One pass does nothing. Thousands of passes, with enough force on one spot, start to damage it. The harder the rub, the fewer steps it takes, and moist skin rubs harder than dry skin.
Stage 2
The patch turns warm, red and tender. Nothing has lifted yet. This is the cheapest moment to act: five minutes, a strip of tape, and you keep walking.
Stage 3
The skin layers have split and filled with clear fluid. The roof of the blister is now the best dressing you have, so the goal changes from preventing it to protecting it.
Stage 4
Keep walking on an unprotected blister and the roof tears, leaving raw skin open to dirt. That is the stage that hurts most and the one most likely to get infected.
Blisters on a hike come from five things: footwear that lets your foot move, damp skin, long days under heavy loads, new boots or out-of-practice feet, and a history of blisters. The first four can be fixed before you leave the house. The last can't, but it tells you exactly where to tape.
Heel lift, toe slide
A boot that's too loose lets your heel lift on every climbing step and your toes slide forward on every descent. One that's too tight presses the same spots on every stride. Either way, the same patch of skin takes the rubbing thousands of times over.
The fix: Fit boots in the afternoon, when feet are biggest, wearing your hiking socks. Snug lacing over the instep stops heel lift.
Sweat, puddles, stream crossings
Moist skin creates more friction than dry skin, which is why a sweaty sock on a hot climb is where most blisters start. Cotton socks hold that sweat against your foot all day.
The fix: Wear synthetic or wool socks and change into a dry pair when your feet are soaked.
Long days, heavy packs
More steps means more rubbing, and a heavy pack pushes your feet harder into your boots on every one of them. Blisters are more likely on long days and under heavy loads.
The fix: Build up to long days instead of jumping straight to one. Tape your known trouble spots before a big mileage day.
Boots and feet that haven't met yet
Stiff new boots haven't softened where your foot bends, and feet that haven't hiked in months haven't toughened either. Skin that's rubbed gently and often adapts and thickens over time, which a first long day doesn't give it a chance to do.
The fix: Break boots in on short walks before a long hike, and never debut a new pair on the big day.
The one cause you can't change
If you've had blisters before, you're far more likely to get them again. In a survey of French trail ultramarathon runners, those with a history of blisters were far more likely to get one in a race.
The fix: You know where yours happen. Tape those spots before you start instead of waiting for the hot spot.
To prevent blisters before a hike, fit your boots with the socks you'll wear, break new footwear in on short walks, pack dry spare socks and paper tape, and tape any spot that has blistered before while you're still at the trailhead. Most of the work happens before the first step.
When you feel a hot spot, stop at once, take the boot and sock off, dry the skin, and cover the warm patch with tape or moleskin before it turns into a blister. Then fix whatever caused it before you walk on. The whole routine takes about five minutes.
The American Academy of Dermatology's advice is to stop as soon as you feel pain or see the skin turn red. A hot spot gets worse with every step, and a few more minutes of walking is often what turns it into a blister.
Look at the spot. Red and warm with no fluid means you caught it in time. If there's already a bubble, skip to protecting the blister below.
Wipe off the sweat and let the foot air out for a minute. Tape won't stick to damp skin, and damp skin is part of why the rubbing started.
Put a strip of paper tape or a piece of moleskin flat over the spot, with no wrinkles.
Change into dry socks if yours are wet, smooth out any wrinkles, and re-lace. A heel hot spot usually means the heel is lifting, so tighten the laces over the instep.
Paper tape is the best-supported way to prevent a blister. Moleskin, hydrocolloid dressings, lubricant, liner socks and antiperspirant each do a narrower job, with weaker evidence behind them.
A systematic review of outdoor blister prevention found little high-quality evidence for most of these methods. Paper tape was the one it rated with moderate confidence.
| Option | What it does | Best for | Evidence |
|---|---|---|---|
| Paper tape | A thin, smooth layer the sock slides over instead of your skin | Taping known trouble spots before you start | Strongest of the lot: 40% fewer blisters in a randomized trial of ultramarathon runners |
| Moleskin | A thicker felt pad that takes the rubbing | Covering a hot spot, or cut into a ring around a blister | Recommended by the AAD; little trial evidence |
| Hydrocolloid dressing | A gel pad that cushions a blister and keeps it moist | A blister that has already formed or torn | Recommended for torn blisters in the clinical literature; the NHS says it may speed healing |
| Lubricant or petroleum jelly | Reduces friction where skin and sock rub | Toes and other spots tape won't stay on | Recommended by the AAD; no strong trial evidence |
| Liner sock under a hiking sock | Moves the rubbing between the two socks instead of against skin | Hikers who blister even in well-fitted boots | Fewer blisters in Marine recruits wearing a thin polyester sock under a thick one |
| Antiperspirant on the feet | Keeps the skin drier | Rarely worth it | Fewer blisters in one study of West Point cadets, but more than half the users got skin irritation |
Paper tape figure from the Pre-TAPED II trial of multistage ultramarathon runners. Antiperspirant figures are from a US Military Academy study of a 21 km (about 13-mile) hike.
Usually not. The intact roof protects the raw skin underneath, and most blisters heal on their own in one to two weeks. The American Academy of Dermatology says draining is only for a large, very painful blister, done with a sterilized needle at one edge, with the roof left in place.
The gear that touches your feet
Socks and fit do more to prevent blisters than anything else. Our sock guide ranks merino and synthetic hiking socks, and the boot and insole guides cover fit and heel hold. The first-aid kit guide says which kits carry blister dressings.
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More on long days and happy feet
Wear boots that fit with the socks you hike in, wear wool or synthetic socks instead of cotton, and put paper tape on spots that have blistered before. Then stop at the first hot spot rather than walking through it. Paper tape has the strongest trial evidence of any prevention method.
Heel blisters usually mean your heel is lifting inside the boot on every uphill step. Lacing snugger over the instep holds the heel down. If the boot is simply too big, no lacing will fix it.
They can. A thin liner under a thicker hiking sock moves some of the rubbing between the two socks instead of against your skin. In a study of Marine recruits, a thin polyester sock worn under a thick one reduced blisters. The AAD suggests a second pair if one isn't enough.
They do different jobs. Thin paper tape goes on before you start, to prevent blisters on spots you know are trouble, and it's the method with the best evidence. Moleskin is thicker and better for padding a hot spot or cutting into a ring around a blister that has already formed.
Usually not. The blister's roof protects the raw skin under it. If it's large and too painful to walk on, the AAD says to drain it from one edge with a needle sterilized in rubbing alcohol, keep the roof on, clean it, and cover it.
Most heal on their own within one to two weeks, according to the American Academy of Dermatology. Keep it covered and avoid the boots that caused it until it heals if you can.
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Skills
In winter the Adirondacks and Catskills go quiet, you can see out through the bare hardwoods, and the spruce on the high summits turn white with rime. Getting started takes skill more than toughness: traction matched to the ground, layers you don't sweat through, and a day planned backward from sunset.
