The First 30 Days

What do people do wrong when they start a new fitness regimen?

Joujon-Roche: They overeat, undereat, eat late, skip meals, don't drink enough water. Those are the big ones. People also carry a lot of guilt. Nothing is worse than eating a bad carb and then feeling guilty about it. If you are going to have the cake, have it with both hands—go in there, roll around in it, love that cake. I can't tell you how many people will drag that cake issue so it ruins their next day. If you fall off the wagon, let it pass.

What can people expect to face in the first month?

Joujon-Roche: Week one, you're full of optimism, new information, new feelings in your body, and you're using new muscles, following a new eating regimen. You're starting to see some results. Life hasn't taken over your schedule yet—you've postponed parties, business dinners, and other commitments.

Week two: You're doing...okay. Clothes fit a bit better already, but the nutrition aspect is hard to maintain because social obligations creep in.

Week three: Expect a plateau—you won't likely be dropping pounds now. You might start feeling negative, but this is the time to keep your head down and show up. Focus on how you feel, not numbers, at this stage.

Week four: This is when you reevaluate your regimen. Ask yourself, What can I do better? What can I do differently? Now increase the challenge.