I would be your buddy for the challenge. I am 30 and a guy with another 90 lbs to go. Starting at 289 and want to get to 180. I too was in great shape when younger, being an avid hiker and taking 3 week wilderness trips while carrying everything in and out. I want to get back to that plus 20 pounds for being older.
I will be in my third week of dieting when this challenge starts, so no water weight to quickly shed. For me to succeed at 4 pounds lost a week, I need to write down everything and stick to the diet. So far for 2 weeks I am 100% on.
The right decision at the right time.