The classic sitz is done cold after you have been heated up first with a hot bath. It is to direct attetnion of flow to that area. It is a signaling device throught temperature change.
for the last 4 days i have been doing 10-20 minute of cold sitz with keeping my body warm. What is interesting, I have broken out with more Acne than i have ever had in my life. I have never had more than 1 or 2 zits at a time ever.. here i am, 31 years old with 6 big zits! weird huh?