I remember lifting weights one time, very little of course. But just that shock gave me a bit of muscle back for a few days and i had a healthier erection and lasted much longer then. Probably at least 15 minutes. Good times of course. Now i can't even go beyond 3 minutes. This was like 4 months ago.
I think for me at least alot is psychological but also some is hormonal. I believe that if i aid my thyroid everything else should come into play.