Quashing The Negative

Today I was feeling kind of blah and really felt just like curling up in bed with the cover over my head. I kept hearing this voice in my head telling me that every one else was working out like mad women/men to win this weight loss contest.(Top Prize is $1000). I did mange to get up and out and walk a mile all the while telling myself that I will do more tomorrow.

Realistically I know that tomorrow I will face that nasty witch in my head that tells me all the negative stuff and then I will have to counter with Ms. Inspiration.

How do you fight the mental challenges of diet and or exercise?