I suspect I may have CFS (and have had it for 20 years, since age 20). I haven't talked to my doctor yet because we suspected it was low testosterone (which I also have, but this is different). Some of the symptoms are: - Post exertion malaise (PEM). This seems to be the big one. I really like to work out, but the more I work out, the more tired I get. It usually happens the day after the workout and lasts a couple days. - In general, I am tired and/or have headaches. But if I don't over exert myself it is not terrible...but is still pretty rough. - At my first real job (age 20), I was totally wiped out after work and headed right for the bed for a 1-1.5 hr nap. Since then, I have needed a nap everyday. As the years went on, I started taking a nap in the car during work. Sometimes twice a day. - Although I tend to sleep a lot (10+hrs a day), I rarely feel refreshed. Sometimes I will feel pretty for a few hours, but it usually doesn't last that long. - This is weird. When I am drinking alcohol and out partying, I usually feel just fine. I thought this may be related to a sleeping issue, but the PEM seems to be a big symptom to look at. I remember even in college that workouts would seemingly wipe me out more than other people. It seems to have gotten a little worse over the years and now I am struggling quite a bit. Does this sound like CFS? It could still be related to my low testosterone, but seeing as I have had this issue since I was young (and no signs of low T then), I think it is something related to either CFS or a sleeping disorder.