When it comes to weight loss, exercise more important for keeping pounds off than diet

AURORA, Colo. — Both diet and exercise are vital to weight loss, but when it comes to keeping off the pounds, a regular workout may pack more of a punch to the gut than what you eat. A new study finds that physical activity is more important than diet in preventing an individual from putting back on any weight they’d already lost.

The research shows that people who have managed to maintain weight loss for a year or more have done so by relying more on exercise as opposed to a strict diet.

“This study addresses the difficult question of why so many people struggle to keep weight off over a long period. By providing evidence that a group of successful weight-loss maintainers engages in high levels of physical activity to prevent weight regain – rather than chronically restricting their energy intake – is a step forward to clarifying the relationship between exercise and weight-loss maintenance,” says study co-author Danielle Ostendorf, a postdoctoral fellow at the University of Colorado Anschutz Health and Wellness Center, in a media release.

Researchers compared a group of 25 previously-overweight adults who’d successfully maintained their weight loss to a group of 27 people already at a healthy weight, along with 28 participants who were still overweight. The “weight-loss maintainers” were people who had lost 30 pounds and successfully kept that weight off for at least a year. Those in overweight group had a body mass index (BMI) that was similar to what the weight-loss group had prior to shedding the pounds.

The authors had participants give urine samples to be used for what they consider the gold standard in precisely measuring one’s total daily energy expenditure, a process known as the doubly labeled water method. This method also gives researchers a strong estimate into energy intake as opposed to simply surveying participants. Researchers also tracked the participants’ daily step count over seven days, and measured their resting metabolic rate to assess energy expenditure from rest versus during exercise.

They found that the total number of calories burned and consumed by those who’d lost weight was much higher — about 300 kcal/day —  than participants in the normal body weight group, but similar to those who were overweight. Yet the amount of calories burned from physical activity by the weight-loss group was higher than both groups, about 180 kcal/day. This demonstrates that they were moving more than the overweight individuals (who naturally have a higher energy cost due to their weight).

To be sure, the authors found that those in the weight-loss group logged about 12,000 steps per day on average. That’s compared to 6,500 steps for the overweight participants and 9,000 steps by those in the normal weight group.

“Our findings suggest that this group of successful weight-loss maintainers are consuming a similar number of calories per day as individuals with overweight and obesity but appear to avoid weight regain by compensating for this with high levels of physical activity,” says co-author Dr. Victoria A. Catenacci, MD, a weight management physician and researcher at CU Anschutz Medical Campus.

The study is published in journal Obesity.

This article was first published on March 30, 2019