Thanks to Dexter Yard for putting this link on my FB page. I wanted to comment on it. So, I am putting it up separately. It is an interesting, but brief, news story. Many runners think their low heart rate is a sign of health and that their hearts will last because they beat more slowly. That is a form of the so many heart beats in a lifetime hypothesis, which is supported only across species, not within a species. I know quite a few runners, and they all boast about their low heart rate. Why does a runners heart beat more slowly and is that good? Is the low rate an adapatation to training or something not so good? And how is the heart rate variability, the most sure sign of a healthy heart, affected? There is nothing in the article about that, but you can be sure that a very low heart rate will also have low variability. This is not good since the heart rate should follow a chaotic series whereas a runners heart is more like a metronome, with a steadier beat and lower variability. Here is what the research found on the heart beat: The vagal nerves lower the heart rate and therefore it was assumed the low heart rate of athletes is the result of over activity of the vagal nerves. But our research shows this is not the case. Actually, the hearts pacemaker changes in response to training and in particular there is a decrease in an important pacemaker protein, known as HCN4, and this is responsible for the low heart rate. The researchers say these molecular changes in the cardiac structure which govern heart rhythm may help us to understand the more frequent occurrence of heart rhythm disturbances or even loss of consciousness in athletes. It may be that the pacemaker protein is depleted or the genetic circuits for synthesizing the protein are damaged. Who knows, but the low heart rate is anything but a positive. Read more: dailymail.co.uk/health/article-2627279/How-craze-running-longer-distances-DAMAGE-heart.html#ixzz31j1biVCD Follow us: @MailOnline on Twitter | DailyMail on Facebook
Posted on: Wed, 14 May 2014 21:15:20 +0000
Trending Topics
Recently Viewed Topics
© 2015