Update post 15: solution found!
I recently found a great group of horse ladies who ride in the south Texas summer heat like fiends - they are great fun, and I’ve gone on 2 longer - 3 to 5 hour - midday trail rides with them.
After which, I have had a mad heat rash on my ankles (area under my socks and a bit above, especially inner ankle). Second time worse than first although ride 2 was the shorter and “cooler” (95 degrees F.) ride. It’s not itchy but sort of stiff, and very unsightly. Angry-looking.
Anyone else get this, and know of any prevention?
In appearance it is very similar to the “hiker’s rash” described on this blog, but can’t be caused by the same thing! And mine is worse than his by a long shot. Takes days to fade away.
http://insuremekevin.com/hikers-rash-red-rash-between-knee-and-ankle-after-hiking-for-several-hours/