This is directed at those who want to seriously improve their tolerance to heat.
I found that heath tolerance will increase significantly with frequent training.
Yesterday and Today I did 50 miles each in 95 degrees and high humidity. (Illinois)
Fluid consumption was five liter per 50 miles. Two liter was Gatorade. ($3. for two L.)
I did both runs at my top speed.
I do daily training on a trainer at 17 MPH purposely in a room without air-condition.
Last year, before this training, I was not able to do this what I described above.