I'm asking because I was recently on an extended boozing session with a lot (fluctuating numbers but 13-17 in total) of lads in the same age-bracket as me (youngest 48, oldest 61). When a couple of women became temporary members of the group, their taxi came and they left and the subject went on to sex and there was a clear dividing line between those who still did it and those who didn't or couldn't. Only one of our group said it was because he was denied it by his partner while of the others who were active and those who weren't, one obvious conclusion emerged. Sport! Those who had led active sporting lives, regardless of the actual sport, were still active while those whose lives revolved around pubs, pies and darts were unanimously inactive. The youngest one of our group admitted to being the longest celibate (nearly 6 years) of those with long-term partners while the oldest was, or claimed at least, to be 'a once a week' man! There will be no surprise to discover that the youngest was clearly the least fit while the elder member still holds age records for his sport.
On the introduction of Viagra, I did some clinical work in the SD area with a different, but related, product and it became apparent that dysfunction was directly related to the arterial health of the patient. Smokers and the overweight were more likely to have (I'm not writing 'suffered' there) SD and if the patient being seen was a low-average weight non-smoker, the first thought was the condition was psychological rather than mechanical.
So I'm raising this question because I'm assuming most on this forum are active and I'm not asking for confessions, just your contributions on this matter.