sarah,

i too started running at about 215 pounds. i was fortunate enough to have a treadmill in my house at the time so i started on the treadmill. i started out with running 1/4 mile and then being done. then i moved up to .5 then .75 and then i finally reached a mile at a time. i never would have guessed then that i would be running for fun now. you just have to keep it slow and steady. and not get discouraged at how difficult it can be to get started. when i take a break from running now sometimes i get discouraged at how much i feel that i backtrack but i just take it slow and regain my momentum in no time. i found the hardest thing about running when i first started doing it, was convincing myself that i could.