U tests how women work off calories

Paul Sanders

To University researcher Katie Schmitz, household tasks considered tedious by some are activities that could provide insight into how women burn calories during their daily routines.
And in the wake of a recent surgeon general’s report on physical activity, Schmitz, a research assistant in the School of Kinesiology and Leisure Studies, is recruiting lean and obese women to participate in the Household Activities, Lean vs. Obese project. The study will start in August.
Women who participate in the study will wash dishes, clean a bathroom and carry groceries while Schmitz measures their heart rates and oxygen consumption.
Schmitz said she would like to extend the study to include men, but has limited funds. “It’s quite sexist of me, assuming that women do most household activities, but I have a fair amount of statistical evidence on my side that women are doing more household chores than men.”
Schmitz said her research is necessary because most obesity studies don’t take into account the different ways lean and obese people burn calories. For the purposes of her study, Schmitz defines lean women as having at the most 25 percent body fat and obese women as having at least 35 percent body fat.
Schmitz, who designed fitness plans for Weight Watchers and has been a personal trainer, said obesity research at the genetic and cellular level is well-funded. But she added, “We really don’t know why some people maintain a high body weight and why some people maintain a low body weight.”
Eating more is not necessarily the reason obese women are heavier than lean women, Schmitz said. “How much you weigh is a balance of how much you eat and how many calories you expend,” she said. “If they’re in balance, then you shouldn’t change weight.”
But Schmitz said reducing the number of calories consumed doesn’t necessarily lower people’s weight if they remain equally active.
Through her study, Schmitz also hopes to discover whether lean and obese people approach household tasks differently.
It may take an obese woman longer to carry groceries up a flight of stairs because of her excess weight, Schmitz said. But it is not clear if that obese woman is burning more, less, or the same amount of calories while performing the same task as a lean woman.
Bob Jeffery, a professor in the University’s Division of Epidemiology, said Schmitz, his former student, is conducting important research because most people’s daily routines are comprised of household activities and not exercise, which has been thoroughly researched.
The Surgeon General’s Report on Physical Activity and Health, released last week, stated that more than 60 percent of American adults are not regularly physically active, and 25 percent are not active at all.
Because the 1996 report lists a number of household tasks as examples of moderate physical activity that can improve a person’s health, Schmitz said, it’s important to accurately measure the calories these tasks burn.
Schmitz said her study will update statistics on energy expended in household tasks.
One of the most widely used tables in exercise research is the Compendium of Physical Activities, which was published by former University researcher Barbara Ainsworth in 1993. Schmitz said the summary is quite comprehensive, but some of its data on household tasks is taken from research conducted in the 1920s.