The short version

Balm prevents skin-on-skin and skin-on-fabric chafing, which is what ruins long days at the thighs, arms and shoulder straps. Toe socks address a specific and common failure, blisters between the toes, which balm alone rarely solves. Carry balm for everything above the ankle; wear toe socks if you get between-toe blisters, and use both for anything very long.

Common questions

How do I stop blisters generally?

Manage moisture, friction and fit. Shoes with room for feet to swell, socks that move moisture, keeping grit out, and dealing with hot spots the moment you notice rather than at the next aid station.

Should I pop a blister mid-race?

Sometimes, and it carries infection risk. If it is affecting your gait it may be the lesser problem, and a clean drain with a sterile needle and a dressing is the usual approach. If in doubt, or if the skin is broken and dirty, see the medical team at the aid station.

When do I apply balm?

Before you start, generously, on every place a strap or limb rubs, and again at aid stations on very long days. Applying after chafing has started helps far less than applying before.

Best general prevention

Body Glide Original Anti Chafe Balm

~$10

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Best for toe blisters

Injinji Run Lightweight Toe Socks

~$20

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At a glance

Body Glide Original Anti Chafe BalmInjinji Run Lightweight Toe Socks
Prevents thigh and arm chafing Yes No
Prevents between-toe blisters Partly Directly
Works under vest straps Yes No
Survives wet conditions Reapply Yes
Needs carrying and reapplying Yes on long days No
Cost Low Low

Choose the Body Glide Original Anti Chafe Balm if…

You are running long enough for skin to rub, which is essentially any ultra. Apply before you start rather than after it hurts, and carry a stick for reapplication, because rain and sweat remove it.

Check Body Glide Original Anti Chafe Balm on Amazon

Choose the Injinji Run Lightweight Toe Socks if…

Your blisters appear between the toes rather than on the heel or ball. Toe socks separate the skin, which is the only reliable fix for that pattern. They feel strange for the first few runs and then unremarkable.

Check Injinji Run Lightweight Toe Socks on Amazon

Related

Comparison based on published manufacturer specifications and the general consensus of owner reports. We have not tested these products side by side. Confirm current specifications and prices before buying. As an Amazon Associate we earn from qualifying purchases, at no extra cost to you.