Napoleon Hill calls Desire "The Starting Point of all Achievement".
Rif said on a Dragon Door post "the MOST important component of any program design is the users incredibly intense desire to achieve the goal the program is designed to produced"
The kind of desire that makes a man post portly pics of himself on his blog is the same desire that results in a 13lb fat loss and and SST increase from 216 to 241 in less than 5 weeks.
It makes you do another set of snatches when you want to lay down and gasp for breath like a fish on the beach.
It makes you order a steak salad and water when everyone around you orders chicken tenders, fries and beer.
It gives you a willingness to sacrifice the thing you think you want right now for the thing you REALLY want overall.
A friend of mine called it "laying your nuts on an anvil and passing out hammers"
It makes you win the toughest competition-the one with the voice of laziness and complancy in your head that say things like "you're already pretty strong, why beat yourself up any more today?"
Then there is the most dangerous one of all: "This one little bit won't hurt, will it?"
Well, if ain't helping, it's hurting. If it doesn't bring you closer to your goal, it takes you a step away.
I believe in listening to your body. If you really don't have it in you today to do what you planned, don't push. You need rest more than you need additional training stimulus. DO NOT however, confuse laziness with the need for rest.
If you have been strict in your diet for 6 day and you want to eat a cookie because it will help you crush a craving and stay on track, go ahead. DO NOT mistake this with giving yourself permission to eat a whole box of cookies, a whole pizza and half a gallon of ice cream.
I follow John Berardi's 90/10 rule- If you stick to your plan 90% of the time, you can intentionally break the rules 10%. In a week this allows me 3-4 opportunities to eat a cookie, drink a couple of beers or miss a meal. It is a part of my plan. It brings me closer to my goal.
Without Desire you are not even going through the motions....you are only pretending to, fooling yourself in the process.
Cultivate your desire. Harness it and direct it toward the thing you really want.