Link between heart arrhythmia and prolonged exercise
EXERCISE may not be as good as we originally thought.
Researchers at the University of Adelaide are investigating a link between people involved in endurance sports, such as running, cycling or triathlons, and an increased risk of heart arrhythmia.
Research leader Dr Adrian Elliott, from the University's School of Medical Sciences, says people don't normally associate healthy activities with an increased risk of heart problems.
"We know that people experience cardiovascular health benefits when they exercise for 30-60 minutes each day, and this is something health professionals encourage people to do, wherever possible.
"However, regularly engaging in exercise beyond the recommended guidelines may have less beneficial consequences on the heart, particularly in the long-term. We're looking for the underlying reasons behind this," says Dr Elliott.
Dr Elliott says the risk of atrial fibrillation - the most common heart rhythm disorder in Australia - is increased almost five-fold in people who engage in regular, prolonged endurance exercise, such as running or cycling.
"The mechanisms underlying this increase in risk are not well understood," he says.
"The risk of atrial fibrillation may be due to changes in heart size that occur as a result of exercise training and/or changes in how the heart rate is controlled.
"Recent findings from studies here at the University of Adelaide indicate that certain areas of the heart may not work as well immediately following prolonged endurance exercise. We've also noticed a slight increase in the frequency of abnormal beats in the upper chambers of the heart.
"More information is needed so we can have a better understanding of what's happening, and then look at what we can potentially do about it."
Runners, cyclists and other endurance sportspeople in the metropolitan area of Adelaide - whether professional or amateur - are now being sought for this study.
Participants will undergo heart rhythm monitoring, a cardiac ultrasound and a blood test.
Do you exercise for longer than an hour each day?
This poll ended on 02 July 2014.
Yes, I do
Sometimes I do
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