I've read a bit about those penis enlargement techniques, and many routines start with warm ups, using hot water. From what I've read, many guys do this warm up under the shower, with a washing cloth, which they wrap around their cocks and balls. I know for a fact that if you do this on a regular basis (say once every two days), you might become infertile pretty quickly. Balls are very sensitive to temperature and they will only produce healthy semen when they experience the correct temperature regularly. We all know that large groups of men are becoming infertile because they watch movies on their laptops, which they place on their genitals (in bed, or on a couch), and because they sit down behind a desk for 8 hrs a day, wearing tight shorts -- this entirely destroys the very fragile temperature balance and reaction of the balls. With disastrous results as a consequence. Moreover, from my biology courses I remember that taking a hot bath makes your semen quasi infertile for the next two days. If you take a hot tub repeatedly, the entire semen producing mechanism and the ability of your balls to respond to temperature changes might become dysfunctional. So be careful with these hot wraps. If you are thinking of ever making kids, don't use them too often.