back in July last year i was terribly out of shape, still am but not as much. I started walking a path that is about 3.5 miles from my door and back to my door. my avg mile was about 22 minutes back then just walking. fast forward to now, i started running as i lost weight, i can do 10 minute miles on treadmill and about 11 minute miles on pavement for about 3-5 miles at a time. when i first started running in november i messed up my knees pretty badly where they didn't really heal until January. not sure if it was my shoes, feet, form, weight or what. went to Fleet Feet in January and had them measure me out and been running once or twice a week since then.

if you're worried about knee, ankle, joint, etc... pain then just walk for a while. i still regularly walk that trail and my walking pace has improved to from 22 minutes per mile to about 16.5 minutes per mile.