I can relate to what happened to ZmeFly... About 5-6 years ago, I developed a blood clot in my leg. I diidn't do anything for a few days, because i thought I just had sore muscles, until my leg was swollen all day long, and felt warm, like a fever. So I went to the ER and they told me "Go home, take a tylenol- you got sore muscles." I went back the next day to complain it's NOT sore muscles, then they finally got around to a sonogram of my leg and figured out it was a DVT. So I went to the Cleveland Clinic and got all the exams they give a 35 yr old guy. Then the doc told me they had to start the I.V. to deal with the clotting, or I might get a pulmonary embolism. I'm OK now, except for some lower leg attrophe from being a couch potato. My VR cycling machine cures that.