In March of 2008 I began treatment for a potentially fatal heart arrhythmia whose cause was unknown. I was fit and healthy, having spent a good part of my adult life as an elite cyclist, much of it racing in Europe.
After 5 years of fence-sitting on the part of my doctors, I have been given a diagnosis of ARVD/C (Arrhythmogenic Right Ventricular Dysplasia / Cardiomyopathy). I lack the known genetic markers for the disease as well as some of the structural changes that accompany ARVD/C, and my condition has shown no indication of being progressive (yet).
There is a growing population of current and former endurance athletes who end up with acquired arrhythmias, and a diagnosis of ARVD/C. But by placing these athletes in the ARVD/C patient population, we are potentially ignoring the very real likelihood of an acquired condition, similar, but different, from ARVD/C.
This blog is written as a resource for athletes with acquired arrhythmias, as well as anyone about to undergo endo or epi-cardial ablation, or the implantation of a ICD. It is also written to help generate some critical mass of interest in support of further research into acquired arrhythmias in endurance athletes and others. Feel free to contact me through the comments page if you have any questions or wish to make a written contribution to this blog.
Friday, January 2, 2009
Endurance sports...the hidden killer??
and cigarettes are good for you...
Lately my blog has been linked to several sites that contain strange anti-exercise screeds or imply in some way that endurance training is detrimental to one's health. One site,CrossFit, seems to be holding me up as some sort of caveat against “too much” endurance training, or maybe the CrossFit guys simply think my blog is cool. Either way let me dispel some myths about my heart condition and endurance training.
As I've said before , there is no reputable science that suggests or concludes that endurance training by itself leads to dangerous arrhythmias, or other heart conditions. A cocktail of conditions may encourage arrhythmias, and there is a very small segment of the population that has a genetic predisposition towards certain heart conditions, (AVRD/C, below) and to those people endurance sports and training can be detrimental in the long term. But for the vast majority of people, endurance sports are simply not going to damage your heart in any way. And to the vast majority of people a modest routine of aerobic endurance training is beneficial for heart health. For those who happen to be crazy about a sport that pushes endurance training to the extreme, as in my sport of bicycle road racing, or marathon running or cross-country skiing, there is nothing deleterious about pushing those limits, as far as heart health is concerned.
If my past behavior had any impact on my current heart condition, it was most likely the times when I raced or trained while sick. I’ve raced in subtropical countries, eaten bad food, drunk bad water, raced through colds and flus and bronchitis. The most likely reason for the scar on my heart that caused my arrhythmia is a viral infection that I was exposed to somewhere along the way. My condition was not caused by the overall training volume of my life to date.
There is a chance (genetic tests are still pending) that I am one of a very few who have a genetic condition known as Arrythmogenic Right Ventricular Displasia / Cardiomyopathy. While, technically, I do have ARVC (Arrythmogenic Right Ventricular Cardiomyopathy), the cause of this condition in most likely not genetic, but rather idiopathic (which basically means that they don’t know for sure). Genetic ARVD/C is a gradual weakening of the walls of the heart through the degradation over time of the muscular tissue. With this condition endurance exercise accelerates the process of degradation. Doctors recommend nothing more than walking, bowling, or golf as activities. Really bad cases of ARVD/C end up as candidates for heart transplant. The disease is still quite unknown, and more is being discovered every day.
Thus far my doctors have been pretty certain that I do not have genetic ARVD/C. There is no cardiac history in my family, and I have only a few of the telltale signs of ARVD/C that show up on an EKG. Even without these indications, I am having the genetic testing done just in case, but I have confidence in my doctors and, since November ‘08, have resumed a modest training program.
Regarding CrossFit and its anti-endurance anti-Long Steady Distance philosophy, I think there is some truth in it at the most basic level. “Specialist” endurance training is not for everyone, and certainly us “specialists” have grave weaknesses in all around fitness (don’t even ask me to do a pull up). But the notion that somehow short, predominantly anaerobic training will make you competitive at anything but the most amateur level in a specialist endurance sport is misguided, nor are most people committed to a specialist sport particularly interested in the kind of fitness CrossFit results in. In the case of bicycle road racing, for example, endurance-overload training effectively recruits fast-twitch muscle for slow-twitch use, extending endurance at the end of a 4 to 6 hr event, thus many road racers limit their anaerobic strength training. Fast to slow twitch muscle recruitment only happens with an LSD program. There are many other effects of LSD endurance training that are necessary to compete at the top level of these specialist sports, but that is a rant for another day...