OK, forget it is not worth it. I am too small and there is no way I could ever grow to be what I want to be. I am even a little crooked! The snow is too deep and I can't see the sun very much. Sometimes I am even covered up.
Do you ever feel like that? Like in order to be healthy you have too far to go?
I would like to suggest--- just start where you are.
Make progress for your health.
The best measure of success is your own improvement.
Take your measurements. See how fast you can walk a mile. See how many sit-ups you can do. Record your diet for a day. Then set a goal and make some changes. Are you improving?
Use that as a motivation and don't compare yourself with Lance Armstrong
(multiple time winner of Tour de France bike race and http://www.sitevip.net/lance-armstrong/career.htm.)
That is like that little twig above getting discouraged because she is not like the picture below.
Go ahead and dream great things.
Then start where you are and make those little changes.
(Wow, this sounds like a Sunday School lesson. You could apply this to repentance also!)