Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New research provides clues as to why elite rowers have bigger, stronger hearts

08.08.2008
Scientists have unravelled a potential mechanism for how top-level rowers develop enlarged strengthened hearts as a result of long-term intensive training.

The research, published in the August edition of Clinical Endocrinology suggests a causal link between naturally occurring hormone levels and strengthening of the heart muscle in professional rowers. Elite rowers were found to have higher levels of insulin-like growth factor 1 (IGF-1) compared to healthy sedentary volunteers. In these athletes, IGF-1 values correlate with enlargement and strengthening of heart muscle cells.

Researchers, led by Dr Giovanni Vitale (University of Milan, Italian Auxologic Institute, Italy) and Professor Gaetano Lombardi (University of Naples Federico II, Italy), measured circulating IGF-1 levels in blood samples from 19 top-level male rowers and 19 age-matched healthy sedentary controls. IGF-1 is a hormone that is produced by the liver in response to growth hormone stimulation.

Each subject had their cardiac structure and function measured using standard echocardiography and ‘pulsed Tissue Doppler’, a more effective way of accessing and recording activity, particularly from the right side of the heart. For the rowers, examinations took place during a period of intense physical training, but at least 24 hours following the last athletic activity.

The rowers had higher serum IGF-1 levels compared to controls, but in both groups IGF-1 levels were within the normal range. The rowers’ hearts were also much larger, showing increased cavity dimensions, increased wall thickness, and enhanced muscle function, in both the left and right sides of the heart, compared to controls. In the rowers, IGF-1 levels correlated significantly with several echocardiographic parameters of myocardial contractility. Importantly, these associations remained significant when adjusted for age and heart rate. There were no significant differences in terms of height, weight and blood pressure between the two groups, although as expected, the rowers had significantly lower resting heart rates compared to the control group.

This is the first study to show an independent association between IGF-1 levels and remodelling of the right side of the heart in competitive rowers, and provides clues as to how the body responds and adapts to prolonged physical exercise. IGF-1 promotes muscle growth, and is known to be activated during exercise; IGF-1 levels often remain elevated following a training period1. This research provides a potential mechanism for cardiac remodelling in rowers, whereby an increase in IGF-1 may activate biochemical pathways, which trigger heart muscle growth, resulting in increased cardiac strength and output.

Researcher Dr Giovanni Vitale said:

“Cardiac hypertrophy, or enlargement of the heart muscle cells, is a hallmark of top athletes, especially rowers, and is a physical adaptation to increased cardiac load during prolonged periods of exercise. Our results show both the left and right sides of the rowers’ hearts are larger, and function at an enhanced capacity compared to those of the controls. The causes of this strengthening of athletes’ heart muscle are not completely clear. It could be due to the production of growth factors (such as IGF-1) during training. In fact, physical exercise is associated with cardiac haemodynamic changes (pressure and volume overload) able to stimulate the production of growth factors by stretching myocardial fibers.”

“To this end, we investigated levels of the hormone insulin-like growth factor-1 (IGF-1), and found significantly increased levels in the rowers compared to the control group, although in both groups IGF-1 levels were within the normal range. Furthermore, higher IGF-1 levels in the rowers’ bloodstream correlated significantly with better heart performance.

These results highlight a possible biochemical mechanism for cardiac hypertrophy in elite rowers and suggest a potentially beneficial role for IGF-1 in the remodelling of the heart muscle. This could mean that naturally increased production of IGF-1, occurring as an adaptation to prolonged training, influences biochemical processes that control contraction of the heart muscle in rowers. Further research is now needed to determine the exact relationship between higher production of IGF-1 and cardiac output in elite rowers.”

Rebecca Dixon | alfa
Further information:
http://www.endocrinology.org

More articles from Health and Medicine:

nachricht Tracking movement of immune cells identifies key first steps in inflammatory arthritis
23.01.2017 | Massachusetts General Hospital

nachricht Team discovers how bacteria exploit a chink in the body's armor
20.01.2017 | University of Illinois at Urbana-Champaign

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: Quantum optical sensor for the first time tested in space – with a laser system from Berlin

For the first time ever, a cloud of ultra-cold atoms has been successfully created in space on board of a sounding rocket. The MAIUS mission demonstrates that quantum optical sensors can be operated even in harsh environments like space – a prerequi-site for finding answers to the most challenging questions of fundamental physics and an important innovation driver for everyday applications.

According to Albert Einstein's Equivalence Principle, all bodies are accelerated at the same rate by the Earth's gravity, regardless of their properties. This...

Im Focus: Traffic jam in empty space

New success for Konstanz physicists in studying the quantum vacuum

An important step towards a completely new experimental access to quantum physics has been made at University of Konstanz. The team of scientists headed by...

Im Focus: How gut bacteria can make us ill

HZI researchers decipher infection mechanisms of Yersinia and immune responses of the host

Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...

Im Focus: Interfacial Superconductivity: Magnetic and superconducting order revealed simultaneously

Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.

While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...

Im Focus: Studying fundamental particles in materials

Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales

Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Sustainable Water use in Agriculture in Eastern Europe and Central Asia

19.01.2017 | Event News

12V, 48V, high-voltage – trends in E/E automotive architecture

10.01.2017 | Event News

2nd Conference on Non-Textual Information on 10 and 11 May 2017 in Hannover

09.01.2017 | Event News

 
Latest News

Tracking movement of immune cells identifies key first steps in inflammatory arthritis

23.01.2017 | Health and Medicine

Electrocatalysis can advance green transition

23.01.2017 | Physics and Astronomy

New technology for mass-production of complex molded composite components

23.01.2017 | Process Engineering

VideoLinks
B2B-VideoLinks
More VideoLinks >>>