Planned, focused exercise may be important in losing weight and keeping it off

It sometimes takes a Herculean effort to lose a great amount of weight, such as sticking to a strict diet and intense exercise regimen. But a new study finds that people who have lost weight may not exercise that much more than people who have never been overweight--but the way they exercise could be different.

Exercise time and intensity was noted among three groups: 34 people who were overweight or obese, 30 people who had never been overweight, and 26 people who had lost a considerable amount of weight and kept it off (most of the participants were women). The last group was part of the National Weight Control Registry, a voluntary registry of people who have lost a significant amount of weight and maintained it.

Test subjects were fitted for a week with accelerometers, devices that record duration, frequency and intensity of movement. Researchers looked at bouts of moderate to vigorous activity that lasted 10 minutes or more, as well as ones lasting less than 10 minutes.

Registry members took part in about 42 minutes per day of sustained moderate to vigorous exercise, while the never-overweight group did about 26 minutes per day of continued moderate to vigorous exercise. The obese group did about 19 minutes per day.

Differences between the registry group and the never-overweight group may not be that significant, according to the researchers, due to the fact that the sample size was so small. However, registry members seem to take part in structured, focused exercise. Time spent in shorter bouts of exercise was the same for all groups.

“Structured exercise may...be important,” the authors wrote, “because activity tends to be at a higher intensity during a sustained bout of activity. It is also possible that planned exercise is needed to achieve the amount of activity required by many individuals to sustain a weight loss.”

Researchers noted that although diet among the test subjects wasn’t monitored, other studies have shown that people who have lost weight and kept it off may eat less fat and fewer calories compared with people who were never overweight.

The study was published online recently in the journal Obesity.