In the many times I've started down the weight loss/running journey I've said that I was not on a diet. I was in the process of changing my life, not just an arbitrary diet "food plan". I still believe that to be very true...and here's why.
Let's say I start a diet plan and am able to stick with it for the year plus that it will take to get to a "goal weight". But, once I'm at the goal weight, then what? Most diets don't allow for a lot of flexibility or variation. That diet was all about losing weight, and I would no longer need to lose weight. So, I will have to go through a process of figuring out what eating is all about again at that weight and activity level.
On the other hand, what if I skipped the idea of diets all together and just focused on eating the proper amount of the right foods. All the while, I'm only adjusting the amount of food needed to support less weight. Once I reach that goal weight, there are absolutely no changes necessary to my "diet" other than to allow for a few more calories because I no longer need to lose weight. Other than that, I will continue to eat the same foods in the same way.
Now let me use the same philosophy to the weight loss itself. I now believe that to truly be successful, I can't afford to focus on weight loss (the number on the scale) as my goal. I need to find proper and measurable goals that will be around long after I reach a goal weight. Again, if my focus is weight loss and I have reached my goal weight, then I no longer have that focus and change is in order to find a new focus.
On the other hand, what if I have a set of continual running goals that were focused on improvement. (Now, let me stop for a second and be clear that I'm not necessarily talking about hard race goals, those will be important in the journey but they are not the journey itself, or the destination). Let's say I had a weekly or monthly goals of increasing mileage, or improving average pace, or improving my fastest mile time. Each would have its own milestone of improvement. Then, once I reach the goal weight, my goals carry on and have a life of their own. Yes they will be a little different over time but the overall goal is continual improvement.
I firmly believe, that when these two ideas (life change instead of diet & continual improvement goals) are married and acted on, I will achieve my "goal weight" (what every that actually is) and more.
But, in the end the one critical thing is that I never give up or quit (if only for a season) but to KEEP MOVING FORWARD!!!!!