Completely different achievement here. Backstory: I was fit as a student: I could climb a 15m rope up with hands only, was completing 5c/6a climbs (French grade), was regularly skating around town and on a karting track, mountain biking my bike up 1000m and freeriding back down...
Then I got a stable relationship, a job, and a car. Before I knew it I grew lazy, fat, weak, and increasingly sad and spiteful. It took me a few years to actually get I was slipping down a dangerous slope and a little more to find I was the only one to blame.
It's been four years and I lost 15kg, slowly, regularly. I can ride again to work without turning into a pouch of water, turned from unable to run 1km without panting to death to running 10km not effortlessly but "easily" nonetheless. Food also improved a lot, both in volume and quality. Net result is I feel healthy again, both in my body and in my mind.
Here's the solution I came up with:
- step 1: make it a habit
- step 2: make it a habit (for real)
- step 3: wait
The first thing is actually getting that I do have the time to take care of myself, if only I want to take it. I bounded that time, just to be psychologically sure of it and not skip. First goal was running 2km without panting. Then running 3km under 20min. At some point of course I could run much longer but it would take more time (not that it was really a problem to do it, but it could become an excuse, the easy way out). So I made running the latter trivial, so that I'd have even less of a reason to skip. Alternatively, if I could not run for some reason I'd do some exercise (abs, push-ups, dips) instead for the same amount of time. Again, the goal was to minimize friction, exercises I could practice anywhere, anytime (e.g for dips I use two chairs), without failing the habit, and not thinking about it. The same basically goes for food, where I traded a high fat, high carb, processed food diet for something much much more balanced.
Also, trigger the high. At some point when running (or whatever) you just feel good because of the adrenaline rush (I may use music to help that, and running outside and focusing on your lesser used senses, especially touch, helps a lot). This is important as it triggers the reward system and helps making it a habit for real (and on step 1 it's really easy to delude yourself into thinking you have made it a habit when you really did not). Yes I'm voluntarily hacking my body to make it dependent on something, for my own good. And now when I skip doing sports or eating properly, I miss it, physically, in a very short time (short enough that the habit never breaks), not enough to feel bad but just enough to carry on. And the next day or the following one, I'm back in my habit.
I still got some work to do to regain original fit but I'm on my way there (extrapolations tell me next year), and now that I'm skateboarding, some even farther day from now I'll land a casper-to-casper (Rodney Mullen is a skateboard hacker[0]) and why not, run a marathon. Everything is possible, it just doesn't happen overnight.
[0] http://www.youtube.com/watch?v=mU7s-opqViM