Study- Fitness most vital in women's health
Sunday, August 18, 2002
Exercise may be better than diet to keep women alive, a study indicates.
Women who were physically fit had a lower risk of death than did sedentary women even if their weight was above currently recommended levels, the study found.
"Fitness is a much stronger predictor of mortality than fatness," said researcher Stephen W. Farrell of the Cooper Institute, a Dallas-based research organization that focuses on exercise.
Farrell and his colleagues looked at data on 9,925 women with an average age of 43 who were given treadmill tests to determine their level of fitness.
The least fit 20 percent were classed as low fit, the 40 percent above that were considered moderately fit and the highest 40 percent were classed as high fit.
Women who tested at the moderately fit level should be capable of walking two miles in less than 40 minutes about three times a week, Farrell said. These women would be able at least to meet the minimum federal recommendations for physical activity, he said. Women at the high-fit level would be able to do a bit more -- walking three miles in less than 45 minutes three or four times a week, he said.
Not hard to meet
Farrell believes it's not that hard to meet the fitness levels in the study. "We think moderate and high fitness are well within the grasp of the overwhelming majority of women," he said.
The women also were classified as being of normal weight, overweight and obese based on body mass index or BMI, which reflects a woman's weight relative to her height. For instance, a 5-foot-4 woman would be normal weight at 128 pounds, be overweight at 159 pounds and be obese at 201 pounds.
The researchers followed the women for an average of 11 years, during which time 195 died.
Moderately and high fit women had about half the risk faced by low-fit women of dying from any cause, Farrell said.
Heart disease risk
The study found indications that excess weight raised the risk of death. The increase did not reach the statistical level at which researchers could say it was meaningful, but other studies have found excess weight increases the likelihood of life-threatening conditions such as heart disease and diabetes.
"We are not saying overweight and obesity are not important health problems. We are saying more attention should be paid to low fitness and changing that," Farrell said.
A study published in August in the New England Journal of Medicine found that even moderate overweight raised the risk of heart failure. The report looked at 14 years of data on 5,881 men and women in the long-running, government-funded Framingham Heart Study.
Beyond the report
However, the report did not consider physical activity levels, said one of the Framingham researchers, Dr. Ramachandran Vasan of Boston University. The measures of fitness used in the Cooper Institute study add information beyond what was reported in his research, Vasan said.
The Cooper Institute findings were published in June in the journal Obesity Research. They are similar to what the institute had found earlier in men, and reported in the Journal of the American Medical Association in 1998. The delay was due to difficulties in finding enough women to study.
"We suspected the findings would be the same but we really needed to confirm that," Farrell said.
It was no foregone conclusion that women and men would have similar results, Farrell said. Hormonally, women are different, and their body composition is different -- they have smaller hearts and fewer oxygen-carrying red blood cells.