American mothers watch more TV and get less physical activity today than mothers did four decades ago, a new study finds.
"With each passing generation, mothers have become increasingly physically inactive, sedentary and obese, thereby potentially predisposing children to an increased risk of inactivity, adiposity [body fat] and chronic non-communicable diseases," said study leader Edward Archer, an exercise scientist and epidemiologist at the University of South Carolina.
"Given that physical activity is an absolute prerequisite for health and wellness, it is not surprising that inactivity is now a leading cause of death and disease in developed nations," Archer noted in a university news release.
The analysis of 45 years of national data focused on two groups of mothers: those with children 5 years or younger, and those with children aged 6 to 18. The researchers assessed physical activity related to cooking, cleaning and exercising.
From 1965 to 2010, the average amount of physical activity among mothers with younger children fell from 44 hours to less than 30 hours a week, resulting in a decrease in energy expenditure of 1,573 calories per week.
The average amount of physical activity among mothers with older children decreased from 32 hours to less than 21 hours a week, with a reduction in energy expenditure of 1,238 calories per week, the researchers found.
The findings mean that mothers in 2010 would have to eat 175 to 225 fewer calories per day to prevent weight gain than mothers in 1965, according to the study published in the December issue of the journal Mayo Clinic Proceedings.
These significant declines in physical activity corresponded with large increases in sedentary pastimes such as watching TV, the investigators noted. On average, sedentary behaviors increased from 18 hours a week in 1965 to 25 hours a week in 2010 among mothers with older children, and from 17 hours a week to nearly 23 hours a week among mothers with younger children.
Compared to working mothers, stay-at-home moms had about twice the decrease in physical activity and much larger increases in sedentary behaviors, according to the report.
The findings provide important insights into the growing problems of childhood obesity and diabetes in the United States, the study authors noted in the news release.
"The confluence of our results and other research suggests that inactivity has increased significantly over the past 45 years and may be the greatest public health crisis facing the world today," Archer said in the news release.
