Ouch.

when i first got my tradmill i bought it used from a guy at work. He had it set with a huge incline and when i fished working out my calfs felt like lead, so much i thought i tore something. When he asked how it was going i told him and he said set the plane to level so it has been ok ever since. Too much of a good thing now atleast the chips dont fall off when i am running.