depends on the person, I wait many hours afterwards .. but saying this I dont do alot of session per week ... only like 3 , so it doesnt effect my, now becoming boring sex life. I belive if you cum right after a session it lowers your hormones like DHT and testostarone which are essential in penile growth ... but peeps say they cum before and after sessions and yet grow fine...so I guess theres no PROOF here from me, but its been said by doctors and urologists that it lowers levels, and chemical changes in the brain ... I belive that SOME males it may effect, like those with low levels of the stuff that need it ... the ones in high mods will be okay to shoot IMHO. I have ALWAYS stood by this rule, of at least 5 hours before or after, it was 8 in the start. But its your choice, s I said others shoot all the time and gain great, even DLD .... but I belive as I said its cos they have high or good levels of hormone, otherwise it MAY effect them.
When I do ejaculate (I try to keep it to 1 per week, max), I wait until at least 3 hours after a session. I don't do it before a session since it really kills my drive to keep going with the exercises in the short term.