It's a New Year and lots of folks are asking us for our resolutions. This isn't the time to make resolutions. Wait until the sometime during the first or second month of the year to make your serious resolutions. In the meantime, if someone asks "Any New Year's resolutions?", just say something like, "I'm going to get out and walk more." They're only making polite conversations anyway. That should satisfy them.
Don't say things like, "I'm going to lose weight." or "I'm going to eat more healthy foods." or anything else on which they can check with you and see that you've failed to follow your resolution.
They won't know whether you're walking more or less.
After January, you can make a pact to yourself to do something like losing weight or eating more spinach (it's ok now).