Re: "Addiction" to exercise
Sara - yes, it does exist. What happens is that after exercising for a few weeks and months (religiously), your body will crave it daily or almost every day. When you sit around, your mind starts to wonder off trying to figure out why you are not running or doing weights etc.
I think thats what they mean by a high. Your body makes certain chemicals thats it starts to want time and time again. The only thing is that in order to get the high, you have to keep doing exercise on a regular basis. It does happen ! Its not a myth :)