I've just spent the past couple days in a panic that I had re-torn my ACL (anterior cruciate ligament) which I had torn playing lacrosse in college - but an MRI just yesterday confirmed that I had just bruised the bone. HUGE relief!! But the stupid knee still hurts, and I won't be able to run on it for a few weeks, at least. And - I had just confirmed with a few friends that I'd be running the San Francisco marathon in August. Arrg! So now that I can't run, all I think about is running, and this article in the NYTimes about the runner's high doesn't help. I'll be over here with an ice pack all day.