People need to know: even without losing weight, you are getting significant benefits by exercising -- you're improving your fitness level, decreasing fat and increasing muscle and improving your lipid panel -- so don't stop exercising.

A second very important message is that subjects enjoyed fitness benefits in the absence of weight loss. Many people exercise with the purpose of losing weight. When they do not lose weight, they do not think the exercise is benefiting them and they stop exercising.

Although our results did point toward amount being more important, it is very likely fitness levels can be improved by increasing either amount or intensity.

The other thing to realize is that people gain 3 to 4 pounds a year, so exercise is really important for weight maintenance.

People find exercise 'hard' and few people want to exercise at an intensity higher than they have to. Walking briskly for 12 miles a week per week is realistic and does not require anyone to incorporate a hardcore training regimen. Increasing your mileage or intensity will give you even greater health benefits.

The cells of obese people remembered their metabolic program, which could help explain, in part, why losing weight and maintaining weight loss is so difficult.