This seems to be the term that is preferred to the cliché "male menopause" when discussing middle age in men. Wiki lists the symptoms as: Symptoms, in humans, caused by a drop in the male hormone testosterone include: Anger and social withdrawal Irritability Hypersensitivity Anxiety Mood swings Depression Hot flashes Lack of libido Back and head aches I seem to be suffering from most of these at the moment; it's getting me down and I'm wondering what to do about it. Worth going to see the GP? There doesn't seem to be any agreement on treatment. Anybody else in their 40s or 50s feeling this way? Does it get any easier? Being very fit is probably mitigating the effects so I wonder how I would be feeling if I was a lardy couch-potato?