you keep doing it, man
no
It's a prescribed Erection! schedule 69
Drinking any alcohol reduces your stamina. Alcohol is a depressant and reduces your responses in every part of your body. Alcoholics are usually impotent.
two or more women depends on the mans stamina
There is no adjectival form of the noun stamina. You would have to recast your sentence. For example:'My friend had enormous stamina when she was running the marathon.''I have noticed that David's stamina has decreased over the past few months.'If you are taking the word stamina to mean high stamina (as opposed to being just a neutral synonym for staying-power, with no indication of how much of it the person in question has), and you want an adjectival equivalent, you could perhaps use powerful or energetic, although they are not exact synonyms.
You bet! Age is not a deterrent - stamina is
The average gay man is virtually the same as the average straight man.
average man.... no.
the average man is 5'10"
There are no patron saints for the average man. All patron saints are, in a sense, for the average man.
That really is up to you. We don't all have the same stamina or the same degree of sexual excitement. Try once a day.