I have had ED for the last few years, mostly because of medical problems and resulting prescription drug treatment of those problems.
One thing I have discovered is that I was sleeping with my penis and testicles 'tucked' between my legs. Since I sleep on my side they were held snugly in place by my legs.
Of late I have started sleeping with penis and testicle outside the front of my legs. Sort of 'hanging' out. My ED seems to have eased up some.
Prior to the change I would very rarely wake up with a morning erection. Now it is common to wake up with at least a partial erection. I suspect that my old method may have been impeding the flow of blood into my penis. With it 'hanging out' the blood can fill it more easily.
If you are having trouble with ED you might give this a try. Please let me know if this works for anyone else.
An unexpected side effect of Aneros usage has been very heightened sensitivity of my entire genital area and my testicles in particular.