U study connects activity, longevity

by Bei Hu

Regular exercise reduces mortality rates in postmenopausal women, according to a study published today by University researchers.
The study, published in The Journal of the American Medical Association, shows mortality rates for postmenopausal women decline as physical activity increases.
“We looked specifically at what the relationship was between reported physical activity in 1986 and the risk of dying over the seven-year follow-up period,” said Associate Professor of Epidemiology Lawrence Kushi, lead investigator of the study.
Researchers concluded that moderate physical activity, such as bowling, golf, gardening and long walks, even done as infrequently as a few times a month, would reduce post menopausal women’s mortality rate by 23 percent.
The rate dropped by 30 percent with participation in similar activity two to four times a week.
“The bottom line … is that women who were (physically) active have lower mortality rates during that specific period,” Kushi said.
Menopause, which occurs when a woman’s ovaries stop producing eggs, spells trouble for many women. Research indicates menopause dramatically increases the chances of developing heart diseases and some forms of cancer.
Women going through menopause also experience a reduction in estrogen production, which can lead to osteoporosis — the loss of bone mass that results in more brittle bone conditions.
The average age for menopause is 51, according to Planned Parenthood Federation of America, Inc. But most American women experience the changes between 45 and 55.
In the United States, more than one-third of all women are over the age of 50, according to American College of Obstetricians and Gynecologists statistics.
Researchers believe more vigorous physical activity, such as swimming, jogging and aerobics, generally holds substantial health benefits. The study’s results suggest that engaging in physical activities once per week reduced postmenopausal women’s mortality rate by 18 percent more than those who only took part in physical activity a few times a month or less.
The research also suggests that physical activity can play a role in bringing down death tolls from cardiovascular diseases. Heart diseases accounted for 33 percent of deaths in America in 1992, according to statistics from the National Center for Health Statistics.
Past studies have explored the benefits of physical activity on health. But most of them were done in men.
“They were offshoots of heart disease studies,” said Kushi. In cases where women were primary subjects, the authority of research results was usually undermined by small sample sizes, he added.
The University project boasts to be one of the largest studies on the relationship between physical activity and women’s health. Researchers surveyed more than 40,417 postmenopausal women, ages 55 to 69, in Iowa starting in 1986. The ongoing study is funded by the National Cancer Institute.
Kushi and his co-researchers chose Iowa as the primary site of investigation in 1986 because at that time the state had a cancer registry, where all local cancer cases were reported.