I love this magical phrase! Heck, I live this magical phrase! We all know "that guy." That guy who's never run a lap in his life but all of a sudden gets a brilliant idea that in order to motivate himself to be fit he'll sign up for a marathon that runs in a month. He trains like hell for 3 days and then gives up because he hurt himself or he's feeling lazy and if he can't run that marathon goal he set for himself, then why bother running at all?
"That guy" is an idiot.
OK, idiot is harsh, let's call him misguided, shall we? The intention is good, the execution is all wrong. What he should do is break his plan down into baby steps.
I'll give you an example of a friend of mine, we'll call him Matt. I would always talk to Matt about how great it felt getting up in the morning and working out before I went to work so, inspired by my waxing poetic, Matt decided to try it himself. The first day, his alarm went off and he was awake but he stayed in bed. The second day he got up but he complained to me that he was a failure because he only worked out for 10 minutes. Man, what a loser, right?
WRONG! This is baby steps at work!!
Instead of beating himself up for only working out for 10 minutes in the morning, I told Matt he should congratulate himself for getting up and working out for 10 minutes more than he did yesterday morning. Then tomorrow he should challenge himself to get up and work out for 20 minutes. Before he knew it, he would be getting up and working out for an hour in the morning and the whole process would be a hell of a lot less painful than Matt was already making it for himself.
Stop trying to go from 0 - 60 in a millisecond. If a Porsche can't do it, what makes you think you should? Pick one goal for yourself that you are going to do for one day. That's it. One day. Don't think about tomorrow or yesterday, focus on this one day. When you achieve this goal for this one day, then take stock of how you feel. Did it make you feel good? Great! Try it again tomorrow but just for TOMORROW only.
Stop overwhelming yourself with the big picture and how many minutes on the treadmill it's going to take you to get there. Yes, you can have an overall bigger goal, but during the process set those mini goals for yourself. It makes habit changing much more manageable, enjoyable, and likely to stick.
What are you going to do today?