Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Marathons damage the hearts of less fit runners for up to 3 months

25.10.2010
V02 max test can help determine who is at risk

Montreal - Is running a marathon good for you or can it damage the heart?

A team of researchers and runners from the Heart and Stroke Foundation have come up with a practical way of answering the question. They used data from magnetic resonance imaging (MRI) to find out what is really going on in the marathoner's heart as the kilometers pile up.

"Marathon runners can be a lot less fit than they think," Dr. Eric Larose today told the Canadian Cardiovascular Congress 2010, co-hosted by the Heart and Stroke Foundation and the Canadian Cardiovascular Society.

Lack of real aerobic fitness may directly impact the ways the heart organizes itself to survive the stress of marathon running, says Dr. Larose.

His research found that the magnitude of abnormal heart segments was more widespread and significant in a group of less fit runners. During the marathon, they had signs the heart might be at greater risk of damage than that of runners who had better training or at least had better exercise capacity.

"Without proper training, marathon running can damage your heart. Fortunately the exercise-induced injury is reversible over time," said Dr. Larose. "But it could take up to three months to completely recover."

They studied the effects using MRI measurements, which propel research beyond the traditional stethoscope as a means of estimating and measuring heart function.

The left ventricle of the heart is divided into 17 segments that make up the heart as a whole. When a segment is injured − or stressed out − during the marathon, its neighbours on either side can take over to perform the function of the damaged area. This makes the heart as a whole appear stronger and fitter than is really the case when considering each individual segment.

It also makes it practically impossible for physicians to arrive at an accurate assessment of the heart health of the marathoner when only considering the whole heart.

"The heart isn't simply playing tricks - this may be an important adaptive survival mechanism, like the way the brain can switch function after a stroke," says Dr. Larose. "Unfortunately, as a result, the data produced by traditional means may be inconsistent and misleading.

"This means that, short of performing MRI in everyone, we are left with only one practical test that can accurately tell runners their level of cardiac fitness under stress, " says Dr. Larose, who is professor of medicine at Laval University and a cardiologist and clinical researcher at Institut universitaire de cardiologie et de pneumologie de Québec (IUCPQ) in Québec City.

That test is V02 max − the ultimate measure of aerobic endurance.

V02 max directly measures body oxygen consumption and it is the best test to provide an accurate measure of a safe maximum heart rate (number of beats per minute) for runners. In V02 testing, treadmills or stationary bicycles may be used to establish cardiac fitness.

Dr. Larose took healthy amateur runners and performed a full evaluation on them six to eight weeks before, and then immediately after, they ran a marathon. They underwent exercise tests, blood analysis, and magnetic resonance imaging.

"What we did notice in this study is a runner with less preparation before the marathon had lower V02 max, so they had lower exercise capacity. Compared to those runners with better training, they became more dehydrated and their hearts showed greater signs of injury. The less well trained runners also experienced greater loss of function associated with lower blood flow and greater irritation of heart segments."

Heart and Stroke Foundation spokesperson Dr. Beth Abramson says that with the increasing popularity of marathon running, especially among boomers who are putting a marathon on their 'to do' lists, runners need to train properly, stay hydrated, and most importantly, speak to their physicians about what is right for them.

"You can do it − physical activity is very important for your heart health. Just be smart about it: train and get medical advice," says Dr. Abramson. "Not everyone will need extensive testing before training to run a marathon but speaking to your doctor about your cardiac risk is important."

Dr. Larose says there is no substitute for a visit to a healthcare professional and, when appropriate, to get the V02 test to measure risks to your heart.

Statements and conclusions of study authors are solely those of the study authors and do not necessarily reflect Foundation or CCS policy or position. The Heart and Stroke Foundation of Canada and the Canadian Cardiovascular Society make no representation or warranty as to their accuracy or reliability.

The Heart and Stroke Foundation (heartandstroke.ca), a volunteer-based health charity, leads in eliminating heart disease and stroke and reducing their impact through the advancement of research and its application, the promotion of healthy living, and advocacy.

Jane-Diane Fraser | EurekAlert!
Further information:
http://www.hsf.ca

Further reports about: Heart MRI Marathon V02 magnetic resonance magnetic resonance imaging stroke

More articles from Health and Medicine:

nachricht Using fragment-based approaches to discover new antibiotics
21.06.2018 | SLAS (Society for Laboratory Automation and Screening)

nachricht Scientists learn more about how gene linked to autism affects brain
19.06.2018 | Cincinnati Children's Hospital Medical Center

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Temperature-controlled fiber-optic light source with liquid core

In a recent publication in the renowned journal Optica, scientists of Leibniz-Institute of Photonic Technology (Leibniz IPHT) in Jena showed that they can accurately control the optical properties of liquid-core fiber lasers and therefore their spectral band width by temperature and pressure tuning.

Already last year, the researchers provided experimental proof of a new dynamic of hybrid solitons– temporally and spectrally stationary light waves resulting...

Im Focus: Overdosing on Calcium

Nano crystals impact stem cell fate during bone formation

Scientists from the University of Freiburg and the University of Basel identified a master regulator for bone regeneration. Prasad Shastri, Professor of...

Im Focus: AchemAsia 2019 will take place in Shanghai

Moving into its fourth decade, AchemAsia is setting out for new horizons: The International Expo and Innovation Forum for Sustainable Chemical Production will take place from 21-23 May 2019 in Shanghai, China. With an updated event profile, the eleventh edition focusses on topics that are especially relevant for the Chinese process industry, putting a strong emphasis on sustainability and innovation.

Founded in 1989 as a spin-off of ACHEMA to cater to the needs of China’s then developing industry, AchemAsia has since grown into a platform where the latest...

Im Focus: First real-time test of Li-Fi utilization for the industrial Internet of Things

The BMBF-funded OWICELLS project was successfully completed with a final presentation at the BMW plant in Munich. The presentation demonstrated a Li-Fi communication with a mobile robot, while the robot carried out usual production processes (welding, moving and testing parts) in a 5x5m² production cell. The robust, optical wireless transmission is based on spatial diversity; in other words, data is sent and received simultaneously by several LEDs and several photodiodes. The system can transmit data at more than 100 Mbit/s and five milliseconds latency.

Modern production technologies in the automobile industry must become more flexible in order to fulfil individual customer requirements.

Im Focus: Sharp images with flexible fibers

An international team of scientists has discovered a new way to transfer image information through multimodal fibers with almost no distortion - even if the fiber is bent. The results of the study, to which scientist from the Leibniz-Institute of Photonic Technology Jena (Leibniz IPHT) contributed, were published on 6thJune in the highly-cited journal Physical Review Letters.

Endoscopes allow doctors to see into a patient’s body like through a keyhole. Typically, the images are transmitted via a bundle of several hundreds of optical...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Munich conference on asteroid detection, tracking and defense

13.06.2018 | Event News

2nd International Baltic Earth Conference in Denmark: “The Baltic Sea region in Transition”

08.06.2018 | Event News

ISEKI_Food 2018: Conference with Holistic View of Food Production

05.06.2018 | Event News

 
Latest News

Graphene assembled film shows higher thermal conductivity than graphite film

22.06.2018 | Materials Sciences

Fast rising bedrock below West Antarctica reveals an extremely fluid Earth mantle

22.06.2018 | Earth Sciences

Zebrafish's near 360 degree UV-vision knocks stripes off Google Street View

22.06.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>