NEW YORK (Reuters Health) - Lower cardiorespiratory fitness and higher body weight are independently associated with the development of type 2 diabetes in women, new research suggests.
"These findings underscore the critical importance of promoting regular physical activity and maintaining normal weight for diabetes prevention," Dr. Xuemei Sui, of the University of South Carolina, Columbia, said in an interview with Reuters Health.
Sui and associates followed 6,249 women between the ages of 20 and 79 years for 17 years. The women were free of heart disease, cancer, and diabetes at the outset.
A total of 143 women developed type 2 diabetes during follow up. After adjusting for a number of factors including body weight, women in the middle and upper thirds of cardiorespiratory fitness, as determined by a treadmill exercise test, had significantly lower risks of diabetes compared to the least fit third.
In analyses accounting for multiple factors including aerobic fitness, women who were overweight had a 2.3-fold higher likelihood of developing type 2 diabetes and women who were obese had a 3.7-fold higher likelihood of type 2 diabetes, compared to normal-weight women.
In an analysis examining the combined effects of cardiorespiratory fitness and body weight on diabetes risk, the researchers found that while aerobic fitness had a protective effect in overweight/obese individuals, it did not eliminate their increased risk.
In a report of the study in the journal Diabetes Care, the investigators note that "obesity and physical inactivity are two major contributors to type 2 diabetes in men and women."
"Given the rapidly growing population prevalence of diabetes, the small improvements in physical activity over the past decade, and the continuing rise in obesity rates, we believe health professionals should consider the potential benefits of greater fitness and aggressively counsel their sedentary obese patients to become more physically active and improve their fitness as a cornerstone of diabetes prevention," Sui told Reuters Health.
SOURCE: Diabetes Care, March 2008.