I have a cast on my foot and it is water proof but I hasn t been drying well and from what I can see my foot is very white and looks like it s wet. it s been like this a couple days and the heal of my foot really hurts and I was looking it up. I think it might be trench foot, what do you think.
HIIT sounds as though the cast is too tight and it's cutting off the blood flow to your foot, so you need to have your doctor look at this.  You may need a fresh cast