This research shows that along with dieting, when overweight women started a new exercise routine after years of being inactive, it didn't really matter whether they came out of the gate running or walking briskly. After a year, there was only a total weight-loss difference of 1 1/2 pounds between them.

"It appears that intensity is not the main factor impacting long-term weight loss," says researcher John M. Jakicic, PhD, director of the Physical Activity and Weight Management Research Center at the University of Pittsburgh.

Exercise As Little as 10 Minutes

It's consistency -- doing some exercise on a regular basis, "even accumulated in bouts of as little as 10 minutes at a time," he tells WebMD.

Jakicic reports that women who started to exercise 200 minutes a week at vigorous levels -- such as running or another activity to leave them panting and sweaty -- shed an average of 19 1/2 pounds after a year, compared with the 18 pounds lost by those spending the same time in more moderate workouts such as walking. Women who exercised 150 minutes a week lost about 15 1/2 pounds with vigorous workouts and 14 pounds at a moderate pace.

Men weren't studied, but Jakicic says there's no reason to believe results would differ in them.

The take-home message: Whatever pace you exercise, do it regularly. "It's best if individuals develop a pattern of exercise that's performed on a daily basis," he tells WebMD.

The Right Exercise

His findings, published in this week's Journal of the American Medical Association, reinforce the often-prescribed recommendations for better health from getting at least 30 minutes of exercise at least five days a week, even if it's at a moderate level. That's important because most dieters give up on exercise programs after a few months, often because they find them too difficult. But by engaging in less strenuous activities such as walking at least a 20-minute-per-mile pace, they may be more likely to continue.

Of course, Jakicic's findings also support that other factor crucial for successful weight loss -- cutting calories.

The 200 women he evaluated, typically 5-foot-4 and weighing 192 pounds when his study began, all cut their calories to 1,200 to 1,500 a day and fat intake to no more than 30% of total calories consumed.

"In this study, they cut calories by almost one-third their previous levels," says I-Min Lee, MBBS, ScD, of Harvard Medical School, who wrote an accompanying editorial to Jakicic's study.

"It's a balance issue. You can exercise very little but eat nothing and still lose weight. It comes down to how much you are willing to sacrifice, in terms of what you eat and what you do to burn it off. Most people don't want to cut their food intake by too much."

Still, Lee tells WebMD that this study shows that a little exercise, done consistently, can do a lot of good.

Pump Up Your Fitness, Too

The researchers also found that all four levels of exercise had the same effect on improving fitness level. Looking at increases in oxygen consumption -- a measure of how well the body uses oxygen for energy -- the researchers found that all four groups had similar improvements after 12 months of exercise.

The Greatest Weight Loss

"You will get the greatest weight loss from changing your caloric intake in the short run," says Jakicic. "However, it appears that without the exercise, the initial weight loss is less and the long-term maintenance of weight loss becomes extremely difficult. So, diet without exercise will make the maintenance of weight loss very difficult."

Conversely, he says that exercise without dieting makes weight loss slow and probably less effective -- especially if you're looking to drop serious poundage.

His recommendation for the ideal combination: "If an individual reduces their current level of intake by 500 to 1,000 calories per day and exercises 30 to 60 minutes a day, the weight loss will be around two pounds per week, on average."

Source: WebMD