I just turned 27 and was close to 330 lbs. My wife had been bedridden for a year due to a back injury and I was feeling really down. I decided to get in shape so I could help my wife even if she never could walk again I would be able to carry her. As of adding this I'm a month away from turning 28 and Down to 283 lbs and have been going to the gym 6-7 days a week since December (3-4 days a week before that) and a Spartan Race is the ideal thing to test my fitness.
I've been over weight for what seems my entire life. I'm using the Spartan Race as a way to change my lifestyle. So far it's working.