Guide · Skin
How to prevent chafing when running
Quick answer
Chafing is skin damage from repeated friction made worse by sweat. Prevent it with fitted, moisture-wicking clothing instead of cotton, a barrier on high-risk areas (balm, petroleum jelly or anti-chafe film), and by changing out of wet kit promptly. Stop and protect the area at the first sign of redness.
- Inner thighs, underarms, groin, nipples and bra or waistband lines are most at risk.
- The AAD advises against cotton because it soaks up sweat and moisture.
- Barrier products reduce friction; film does not wear off mid-race.
- Treat red skin early, before it breaks.
What causes chafing
MedlinePlus lists the usual causes: friction, coarse fabric, repetitive movements like running and cycling, and dried sweat.[2] Sweat makes skin softer and increases friction, and as it dries, salt crystals add abrasion. Over hours, the outer layer of skin wears through.
Areas most at risk
Inner thighs, underarms, the groin, nipples, under sports-bra bands, waistbands, and for triathletes the back of the neck from the wetsuit collar.
How to prevent it
- Clothing: fitted, moisture-wicking technical fabric. The AAD notes that cotton soaks up sweat and moisture, which can lead to friction and chafing.[1] Running tights or longer shorts protect inner thighs.
- Barriers: petroleum jelly, anti-chafe balm, powder or a film over the problem area. MedlinePlus recommends barriers on inner thighs and upper arms.
- Anti-chafe film: a thin layer that skin slides over, designed to last a long race without reapplying.
- Nipples: use nipple guards or tape.
- Change promptly: get out of wet, sweaty clothes after the session.
If you have chafed
Rinse with lukewarm water, pat dry and leave the area uncovered or loosely covered while it heals. Do not put adhesives over broken skin. See a doctor if it does not improve or shows signs of infection.
FAQ
How do you stop inner thigh chafing when running?
Wear running tights or longer shorts, keep skin dry, and cover the inner thighs with anti-chafe film or a barrier balm before you start.
Is Vaseline good for chafing?
Petroleum jelly is a common barrier for runs up to a few hours. In long or wet races it may need reapplying, which is where films and guards help.
Sources
- How to prevent and treat blisters. American Academy of Dermatology.
- Chafing. MedlinePlus, US National Library of Medicine.