As part of the Integrative Cardiac Health Project at Walter Reed Army Medical Center, Washington, D.C., researchers analyzed the sleep, activity, and energy expenditures of 14 nurses who had volunteered for a heart-health program. The program included nutritional counseling, exercise training, stress management, and sleep improvement. Each participant wore an actigraphy armband that measured total activity, body temperature, body position, and other indices of activity and rest.
When we analyzed our data by splitting our subjects into short sleepers and long sleepers, we found that short sleepers tended to have a higher BMI, 28.3 kg/m2, compared to long sleepers, who had an average BMI of 24.5, said lead investigator Arn Eliasson, MD, in a news release.
Surprisingly, overweight individuals tended to be more active than their normal-weight counterparts, taking significantly more steps than normal-weight individuals: 14,000 compared to 11,300, a nearly 25% difference, and expending nearly 1,000 more calories a day 3,064 versus 2,080. However, those additional energy expenditures did not manifest in reduced weight.
Higher perceived stress may erode sleep. Stress and being less rested may cause these individuals to be less organized than normal weight individuals, meaning they would have to make more trips and take more steps to accomplish the same tasks. This might add to their stress and encourage other unhealthy behaviors like stress eating, said Eliasson.