Higher duration and intensity of exercise may improve long-term weight loss.
In this study, researchers from the United States compared the effects of different durations and intensities of exercise on 12-month weight loss and cardiorespiratory fitness.
Between 2000 and 2001, the team evaluated 201 sedentary women with a mean age of 37 years and a mean body mass index of 32.
The team randomly assigned the study participants to 1 of 4 exercise groups.
|Mean cardiorespiratory fitness levels increased significantly in all groups.|
|Journal of the American Medical Association|
Exercise groups were based on estimated energy expenditure and exercise intensity.
All participants reduced their energy intake to between 1200 and 1500 kcal/day and their dietary fat to between 20% and 30% of the total energy intake.
Overall, the doctors evaluated 184 women over a 12 month period.
They found, using intention-to-treat analysis, that mean weight loss following 12 months of treatment was significant in all exercise groups. There was no significant difference between the groups.
In addition, mean cardiorespiratory fitness levels also increased significantly in all groups. Again, the team found no difference between the groups.
Post hoc analysis revealed that percentage weight loss at 12 months was associated with the level of physical activity performed at 6 and 12 months.
Participants reporting less than 150 minutes of exercise per week had a mean weight loss of 5%, while those with an inconsistent pattern of exercise mean weight loss was 7%. For those reporting more than 150 min/wk mean weight loss was 10%, and for those reporting 200 min/wk or more of exercise mean weight loss was 14%.
Dr John Jakicic's team concluded, "Significant weight loss and improved cardiorespiratory fitness were achieved through the combination of exercise and diet during 12 months".
However, "No differences were found based on different exercise durations and intensities in this group of sedentary, overweight women".