Exercise alone is not the answer.

• Position: Weight Loss

A sedentary lifestyle may contribute to a person's weight problem, but for losing unwanted pounds, exercise is no substitute for consuming fewer calories, contends Weight Watchers International, Inc., Woodbury, N.Y. Consider the following:

* Current recommendations call for adding 30 minutes of moderate activity at least four days a week. The majority of Americans fail to meet this goal.

* To maintain current weight while adding to caloric intake, an individual needs to exercise enough to burn about 5 1/2 calories per pound per day. For an adult weighing 170 pounds, that's 925-950 calories, which is roughly equivalent to walking nine to 10 miles, raking for four hours, vacuuming for three hours, or practicing yoga for 3 1/2 hours.

* For each pound lost through exercise alone, a person needs to burn an additional 3,500 calories. That means a 170-pound adult would need to walk another five to 10 miles per day (or a total of 14-20 miles per day) to lose one to two pounds per week.

* Most experts agree that physical activity modestly contributes to weight loss and should be part of a comprehensive weight loss program that achieves an overall energy deficit of 500 to 1,000 calories per...