|
female professional dancers face the
same health risks as young female athletes when they don't eat enough to
offset the energy they spend, and stop menstruating as a consequence.
"These two components of the female athlete tetrad put
them at higher risk for the other two; the cardiovascular and bone
density deficits of much older, postmenopausal women," according to Dr.
Hoch, associate professor of orthopaedic surgery and director of the
Froedtert & the Medical College Women's Sports Medicine Center.
The researchers studied 22 professional ballerinas,
all members of the Milwaukee Ballet Company, to determine the prevalence
of disordered eating, amenorrhea (lack of menstruation), abnormal
vascular function and low bone density. Study findings were presented at
the American College of Sports Medicine meeting in Seattle, May 30.
The dancers completed questionnaires on their
menstrual patterns and eating habits, and underwent a blood test for
hormonal levels. Thirty-six percent of the group had disordered eating
habits and 77 percent were in a calorie deficit. Twenty-seven percent
were currently amenorrheic, 23 percent had low bone mass density and
nine percent were taking birth control.
Arterial ultrasound measurements revealed that 64
percent had abnormal artery dilation in response to blood flow.
"It was unknown if professional dancers without
menstrual periods have evidence of vascular dysfunction, yet some
characteristics of the tetrad were common in this group," says Dr. Hoch.
"Eighty-six percent had one or more components, and fourteen percent had
all four."
The study was funded by grants from the Clinical and
Translational Science Institute Adult Translational Research Unit of the
Medical College, and by the Steve Cullen Healthy Heart Club Funding of
2008.
Co authors of the study include: Paula Papanek, Ph.D.,
associate professor and director of exercise science at Marquette
University; and at the Medical College - Heather Havlik, M.D., a sports
medicine fellow; William Raasch, M.D., professor of orthopaedic surgery;
Michael Widlansky, M.D., assistant professor of medicine in cardiology;
Jane Schimke, clinical research coordinator, and David Gutterman, M.D.,
senior associate dean and professor of medicine in cardiology.
High-dose Folic Acid Supplements Improved Vascular
Function in Amenorrheic Runners
In a related study, presented earlier at the American
Society of Sports Medicine meeting in Tampa, Fla., researchers at The
Medical College of Wisconsin in Milwaukee found that four to six weeks
of high-dose folic acid supplementation could improve vascular function
in young female runners who were amenorrheic (not menstruating).
This is the first study to use folic acid
supplementation to improve vascular function in young runners, and is
important because folic acid may not only decrease cardiovascular risks
but also improve athletic performance for these women. The research was
conducted at Froedtert Hospital.
"Previous studies have shown that amenorrheic women
runners have decreased dilation in the main (brachial) artery of the arm
in response to blood flow," says lead author Stacy Lynch, M.D., a
women's sports medicine fellow at the College. "Athletic amenorrhea has
a hormonal profile similar to menopause, when the earliest sign of
cardiovascular disease is reduced vascular dilation, which can limit
oxygen uptake and affect performance."
While the benefits for women of an active lifestyle,
including running, are profound and well-known, there are nearly three
million girls in high school sports and approximately 23 million women
who run at least six times a week. The prevalence of athletic-associated
amenorrhea among these runners is now estimated at 44 percent.
The researchers recruited 16 female college or
recreational runners, ages 18 to 35, who were not on birth control pills
and had been running at least 20 miles a week for the past 12 months.
These included six otherwise healthy women with reduced vascular
function and irregular or absent menstrual periods, and a control group
of ten with normal periods. Their vascular function was measured before
and after treatment with 10 mg/day of folic acid for four to six weeks.
Vascular function returned to normal in the amenorrheic women after
folic acid supplementation, and it remained at normal levels in the
control group despite supplementation.
Both children and adults require folic acid to produce
healthy red blood cells and prevent anemia. Folic acid, also known as
vitamin B9, folacin and collate, is the form of the vitamin needed
during periods of cell growth. |
