Leg rash and cycling pants

[Kat1015]

I'm having an ongoing problem with leg rash associated with cycling shorts.  The rash occurs on the front of my thighs, both above and below the leg bands.  I always wear sunscreen, and have recently tried Slide, purchased from our bike shop (it does not help).  The rash is bright red, blotchy, and does not itch, but feels like a sunburn.  Some of the areas are slightly raised, but no pustules form.  The rash is bright red the day after riding, then gradually fades over the next 4-7 days.   My family practitioner and dermatologist have looked at the rash soon after it appears, and have no idea what could be causing it.  I am not taking any medications that cause photosensitivity, and the rash does not occur on other parts of my body, or at any other time.  This problem first occurred when I was living in the upper midwest, and occurs now that I'm living in Florida.  
Any thoughts/ideas would be greatly appreciated!


This discussion is related to Rash Appeared on Legs.

[Meanman]

Theres a good chance that its the Lycra in the short. Have no none allergies ,went thought all the BS & came up clean. Started happening to me about a years ago at the 3hr part of my rides. Tried wearing Nike compression short under the bike shorts to minimize contact & I did have some success  

[Kat1015]

It is still a mystery to me.  I have continued to have the problem, regardless of what I have tried.  But..........perhaps a breakthrough!
This past week  I bought a pair of Pearl Izumi 3/4 tights, SPF 50.  They come to  just below the knee.  Although I've only had one ride wearing the tights, I am happy to report that the rash was in fact MUCH less severe than usual.  It was a hot sunny day, the ride length was my normal 30 miles on the same trail as in the past.  The only other difference was that I did not apply sunscreen on the thighs (covered areas).  I always apply sunscreen to all exposed areas, and do not experience the rash  anywhere else on the body.
I will let you know how future rides go!

[cmbuzz]

Has anyone found out what this is?

I always thought it was an allergic reaction to the sun. I only seem to get it on hot sunny days (while cycling). I used to think it was when I didn't wear sunscreen but it also happens when I do.

Here's a pic after a long day with no sunscreen.

http://www.crazyguyonabike.com/doc/page/pic/?pic_id=663655

I also wear pearl Izumi with the grip rolled up.

My doctor once said it could be an allergic reaction to my sweat, don't know if I believe that because it only happens when cycling in the sun and heat.

[ryoung36]

Same thing is happening to me. Right below the cycling shorts. Been riding 200-300 miles per week in preparation for Ironman Florida and it pops up on long rides. Going to see a dermatologist if I can get in...

[Suz9919]

I have experienced the same thing on long/hot rides, with it getting worse the longer/hotter the ride.  At first I thought it was heat rash, but it doesn't resolve for a few days and looks more like an allergic reaction.  I have several pairs/brands of tri shorts and it happens with all of them.  Silicone allergy is extremely rare, but I wonder if it could be some kind of adhesive or additive (could there be any latex?).  REALLY hoping to figure out how to prevent this before my first ironman in August -- it will be HOT and I will be wearing the tri shorts for a long time!

[shortcut1]

I have just recently begun experiencing this same problem.  I just bought new bike shorts and the rash has been on both legs.  I am getting ready to go back to using my old shorts but, for anyone suffering from this, I have found that GoldBond powder clears it up almost completely the same day I have riden.