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PUBLIC RELEASE DATE:
9-Apr-2003

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Contact: Donna J. Krupa
djkrupa1@aol.com
American Physiological Society
@phyziochick

Caffeine-herbal ephedra combination alters cardiovascular response prior, during and after exercise

New study results demonstrate why caffeine and ephedra may provide a 'final boost'

April 9, 2003 (San Diego, CA) -- After Baltimore Orioles pitcher Steve Bechler died during spring training earlier this year, the spotlight again turned on the dietary supplement ephedra. The Chinese herb, used for asthma in the 1960s, is attractive to athletes, because it provides and energy "boost" during games, and offers pound-dropping qualities (an attraction for Bechler, who was ten pounds overweight).

Ephedra has been linked to almost 100 deaths, among them high school and college athletes who have collapsed during games or practice. The supplement is banned from the National Football League (NFL), National College Athletic Association (NCAA) and the Olympics, but not from major league baseball. Even before this high profile death, ephedra was viewed with caution. For example, even thought the supplement makes up less than one percent of herbal supplement sales, the Food and Drug Administration (FDA) believes ephedra causes 64 percent of all reported side effects from herbs.

Controversy and Confusion
The controversial herb could be found in the energy supplement, now discontinued, called "Yellow Jackets." These "energy boosters" contained 520 mg of Ephedra Extract (supplying 25mg ephedrine alkaloids), Kola Nut Extract (supplying 200mg caffeine alkaloids), White Willow Bark, and Chromium Picolinate. The University of Memphis labeled such combinations "deadly." However, the International Journal of Obesity stated in its May 2002 issue that "The combination of ephedra and caffeine is safe and effective for weight loss."

A New Study
Against this backdrop, a team of researchers set out to examine how ephedra and coffee could impact on health. The authors of the study "Caffeine-herbal Ephedra Combination Alters the Cardiovascular Response Prior to, During, and Following Exercise," are Tasha P. Ballard and Matthew D. Vukovich, both from the South Dakota Health Promotion and Research Program, South Dakota State University, Brookings, SD. They will present their findings at the upcoming meeting, Experimental Biology 2003, being co-sponsored by the American Physiological Society (APS). More than 7500 scientists and researchers are expected to attend the meeting, being held April 11-15, 2003, at the San Diego Convention Center, San Diego, CA.

Methodology
Caffeine-naïve subjects (five men and five women) were studied at rest, during exercise, and recovery after the ingestion of either a placebo or 150mg caffeine/20mg ephedra. Key physiological measurements (blood pressure, VO2, hypersensitive response) were made prior to, and 30 and 60 minutes following after the administration of supplements.

Results
Hypersensitive response was higher at 60 minutes rest in caffeine/ephedra subjects and remained higher at 30 and 60 minutes of exercise. Additionally, those taking the supplements registered higher systolic blood pressure during rest. Mean arterial pressure also measured higher in the caffeine/ephedra group.

Conclusions
Those ingesting caffeine and ephedra prior to exercise will alter the cardiovascular system by increasing hypersensitive response prior, during, and after exercise, and systolic blood pressure before exercise. The higher rate pressure indicates greater demands on the heart when individuals consume caffeine and ephedra.

The American Physiological Society (APS) is one of the world's most prestigious organizations for physiological scientists. These researchers specialize in understanding the processes and functions underlying human health and disease. Founded in 1887 the Bethesda, MD-based Society has more than 10,000 members and publishes 3,800 articles in its 14 peer-reviewed journals each year.

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Contact: Donna Krupa@ 703.527.7357 (vm)
Or 703.967.2751 (cell) or djkrupa1@aol.com
Through April 10th, 2003

NEWSROOM OPENS @ 7:00 AM PST
APS Newsroom: April 11-15, 2003
San Diego Convention Center
Hall A (Flex Unit)
Telephone: 619.525.6340 or 6341



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