I always wake up with great erection but the moment I start walking to the bathroom it disappears completely.

I also noticed that when I sleep on the sides the erection is even better but I thought that it has something to do with gravity and venous work or I don’t know. But now reading this site I think that there may be other explanation. Is it?

George

ANSWER
Indeed, there is another explanation.

The problem is that once you stand up your nerves, muscles, and joints demand additional blood flow and androgen hormones for a vital functional support. If you’re experiencing lessened concentrations of androgen hormones in the blood they will be drawn away from your pelvic area, leaving you powerless to support the erection.

The sleeping you describe gives you stronger erections because it relaxes your spine and no hormones or neurotransmitters are needed to support additional functions.