HOME >> MEDICINE >> NEWS
Caffeine limits blood flow to heart muscle during exercise

In healthy volunteers, the equivalent of two cups of coffee reduced the body's ability to boost blood flow to the heart muscle in response to exercise, and the effect was stronger when the participants were in a chamber simulating high altitude, according to a new study in the Jan. 17, 2006, issue of the Journal of the American College of Cardiology.

"Whenever we do a physical exercise, myocardial blood flow has to increase in order to match the increased need of oxygen. We found that caffeine may adversely affect this mechanism. It partly blunts the needed increase in flow," said Philipp A. Kaufmann, M.D., F.A.C.C., from the University Hospital Zurich and Center for Integrative Human Physiology CIHP in Zurich,.

The researchers, including lead author Mehdi Namdar, M.D., F.A.C.C., studied 18 young, healthy people who were regular coffee drinkers. The participants did not drink any coffee for 36 hours prior to the study testing. In one part of the study, PET scans that showed blood flow in the hearts of 10 participants were performed before and immediately after they rode a stationary exercise bicycle. In the second part of the study, the same type of myocardial blood-flow measurements were done in 8 participants who were in a chamber simulating the thin air at about 15,000 feet (4,500 meters) altitude. The high-altitude test was designed to mimic the way coronary artery disease deprives the heart muscle of sufficient oxygen. In both groups, the testing procedure was repeated 50 minutes after each participant swallowed a tablet containing 200 milligrams of caffeine, the equivalent of two cups of coffee.

The caffeine dose did not affect blood flow within the heart muscle while the participants were at rest. However, the blood flow measurements taken immediately after exercise were significantly lower after the participants had taken caffeine tablets. The effect was pronounced in the group in the high-altitude chamber.
'"/>

Contact: Amy Murphy
amurphy@acc.org
301-581-3476
American College of Cardiology
13-Jan-2006


Page: 1 2 3 4

Related medicine news :

1. New research explores limits of non-invasive coronary imaging tests
2. Defining the limits of computerized physician order entry systems
3. Study shows schizophrenia limits understanding of body language
4. A Jekyll and Hyde of cytokines: IL-25 both promotes and limits inflammatory diseases
5. Health professionals believe gender bias limits womens progression in NHS
6. Immune system lab model overcomes ethical limits on human hematopoietic stem cells studies
7. Even low levels of weekly exercise drive down blood pressure
8. Chemotherapy with bevacizumab increases risk of blood clots in arteries
9. High blood pressure problems largely misunderstood by sufferers
10. Trial stops after stroke and mortality significantly reduced by blood
11. Program announced to improve care in developing areas for patients with blood disorders

Post Your Comments:
*Name:
*Comment:
*Email:


(Date:6/24/2016)... ... ... a crisis. Her son James, eight, was out of control. Prone to extreme mood shifts ... upset him, he couldn’t control his emotions,” remembers Marcy. “If there was a knife ... and say he was going to kill them. If we were driving on the ...
(Date:6/24/2016)... ... 24, 2016 , ... Global law firm Greenberg Traurig, P.A. announced that 20 ... by their peers for this recognition are considered among the top 2 percent of ... honors as members of this year’s Legal Elite Hall of Fame: Miami Shareholders ...
(Date:6/24/2016)... (PRWEB) , ... June 24, 2016 , ... Comfort Keepers® ... American Cancer Society and the Road To Recovery® program to drive cancer patients to ... and other adults to ensure the highest quality of life and ongoing independence. ...
(Date:6/24/2016)... ... 2016 , ... People across the U.S. are sharpening their pencils and honing ... contest in which patients and their families pay tribute to a genetic counselor by ... Society of Genetic Counselors (NSGC) Annual Education Conference (AEC) this September. , In ...
(Date:6/24/2016)... ... 24, 2016 , ... The Haute Beauty Network, affiliated with ... as a prominent plastic surgeon and the network’s newest partner. , Dr. ... handsome men, look naturally attractive. Plastic surgery should be invisible.” He stands by ...
Breaking Medicine News(10 mins):
(Date:6/24/2016)... FRANCISCO, Calif. , June 24, 2016 /PRNewswire/ ... ), a biopharmaceutical company developing novel therapeutics for ... unmet needs, today announced the closing of its ... of common stock, at the public offering price ... in the offering were offered by GBT. GBT ...
(Date:6/24/2016)... , June 24, 2016 The Academy of ... recommendations that would allow biopharmaceutical companies to ... entities that make formulary and coverage decisions, a move ... of new medicines. The recommendations address restrictions ... appear on the drug label, a prohibition that hinders ...
(Date:6/24/2016)... -- According to a new market research ... Safety Pen Needles), Needle Length (4mm, 5mm, 6mm, 8mm, ... Purchase (Retail, Non-Retail) - Trends & Global Forecasts to ... for the forecast period of 2016 to 2021. This ... 2021 from USD 1.65 Billion in 2016, growing at ...
Breaking Medicine Technology:
Cached News: