I started c25k at 286 lbs and I completed it weighing 255 and I'm only 6ft tall so I was what you would call obese just stick with it I know it sucks sometimes just push through it and you will be thank full even at 255 I can run a 5k fairly easy so I'm moving on up to the 10k would love to lose about another 40 lbs so I can look sharp for my 10 year anniversary if you ever need someone to talk with motivate or whatever hit me up