Tuesday, March 31, 2009

Are Triathlons Deadly?

Ironic that only 24 hours after I posted "Is Too Much Exercise Bad For You?" that the Associated Press came out with an article "Triathlons Pose Deadly Heart Risks" . The media is swarming all over some recently released research studies, warning that triathlons cause a higher risk of a fatal heart attack than marathons. Obviously, this warrants a closer look.

First, the studies found that newbies (aka weekend warriors) were more at risk. This makes sense. Your body isn't used to the demands of your new training program. That's why doctors always recommend getting checked out before starting new exercise. Exercise is only good for the heart after several months of consistent, frequent training because it strengthens the heart. The heart is a muscle--aerobic exercise is like weight lifting for the heart. But just like doing bicep curls, you have to break down the muscle a little first before it builds back up and gets stronger. So to make your heart stronger, you have to stress it. Meaning that if you're new to triathlon or working out, and you have an underlying heart problem that hasn't given you symptoms yet because you've been a sedentary couch potato, and you suddenly start running 10 miles, the chance of your heart going "WTF?" and conking out is much higher.

Secondly, probelms usually occur at the very beginning of the triathlon, in the water. The shock of cold water constricts blood vessels, stressing the heart, not to mention all the adrenaline from the thrill right before the start of a race, causing the heart rate to skyrocket.

Finally, on a blog post by Dr. John Martinez at Coastal Wellness, he takes a closer look at the study:
"Do Triathletes Have a Higher Risk of Heart Attacks?"/

First, note that it's a "retrospective" study, meaning that the researchers tried to make sense of an occurrence after it's happened (usually not very meaningful on it's own but can lead to the design of future, better studies with hypothesis-driven questions).

Second, the study looked at "all deaths" not just cardiac-involved ones. Of the 14 deaths included, 1 occurred due to a bike accident, and autopsies were only performed on 6 of the others. Of these 6, 4 showed signs of underlying heart disease. Since I study heart disease, I wonder how many of these patients with heart disease were age-related. I highly doubt triathlon caused the heart disease. As a matter of fact, triathlon (or any exercise) can delay or reverse the damage caused by heart disease (usually caused by sedentary lifestyle and poor diet resulting in high blood pressure, triglyceride and cholesterol). Second, there is no evidence the deaths occurred because of heart problems (heart disease can be asymptomatic for a long time).

Dr. Martinez says,
"However, the reality is that these individuals that did have cardiac events during the triathlon probably had significant cardiac disease despite their triathlon lifestyle..."
--and I have to concur.

Here's a great article
that looks at the cause of cardiac-related deaths during exercise:
"Exercise-associated acute cardiac events generally occur in individuals with structural cardiac disease."

Here's another article
taking a look at the risk/benefits of marathon training:

8 comments:

Backpacker said...

Interesting topic and I like your analysis. On one of my first tris, a guy who looked just like me died on the swim. My wife thought it was me until they cut his wetsuit off. All I thought was, "why are they bringing in an ambulance" and "hope they don't wreck my time over this." Going to hell for sure.

Chad in the AZ Desert said...

I think you and Dr. Martinez are right on the money with this. No matter what, I will hold to the fact this it is healthier to be an endurance athlete than to not be one and all these misquoted studies in the press do is prevent people from potentially changing their lives for the better.

teacherwoman said...

I have read that article as well. Very interesting. I too agree with you and Dr. Martinez.

Grey Beard said...

I had a "coronary event" in late '04 and ended up getting an angiograph in the 3rd hospital. The enzyme test was negative, but the trace was markedly different than a 10-day old stress EKG trace, so not an imagined event nor panic attack. (I also have a right bundle-branch block)

The Dr told me I had the heart of a 20-yr old, no plaque in my heart, aorta, or lungs, but I still had chest pain and high blood pressure.

Kaiser was spending millions telling people on TV how much they wanted people to be well and live healthy lifestyles, but when I asked them month after month if it was safe for me to return to the gym they said I was on my own and they wouldn't sign me off for that.

I finally changed gyms, lied my butt off and went back, because if you don't, at some point the whole coronary disease thing becomes a giant self-fulfilling prophesy. It seriously pissed me off that I had to take all of the risk by myself, make the decision on my own with little info to go on, and bear any health or financial outcome on my own. I did it anyway, because in the end you can choose life, or you can chose death. There is no try.

I put up with chest pains for 2 more years until I started taking 400mg of Co Q10 a day in late '06 and my chest pains went away. On the treadmill in the gym I could take my heart up to 162bpm, about 15bpm higher than before. I don't think you can fake that kind of result. From that day forward I have continued to push myself slowly but persistently to higher fitness levels. Last year about this time I stated cycling again after almost 25 years off. It's the best health decision I've ever made. I no longer have chest pains, and stopped taking Co Q-10 8 months ago.

I will be the first to admit that I enjoy riding and "racing". I am competitive. It's who I am. If, God forbid, my heart blows up and I end up dead I'm happy with that trade-off. I'm not risking my life (or others) street racing or eating chicken wings and ribs in front of a giant TV while I grow a huge ass. I am living.

Tens of thousands of people die each year in car accidents and people just shrug. Millions die of sedentary life-style diseases, now the most prevalent form of disease in the western world, and that is seen as perfectly acceptable. I refuse to explode my liver with statins or throttle my heart with Beta blockers - preferring instead to put it to work doing what it was intended to do - fuel intense exercise. Instead, I spend the same money on a bike and events and live a healthy and vital life I love.

If the choice is between managing disease until an inevitable death from drug-destroyed organs because the drug companies need to sell you a pill each day to create reliable profits, (Ever since the pill turned out to be a huge cash-cow the drug companies have been obsessed with finding crap you HAVE to take each day so their stream of profits is endless. They are every bit as insidious and despicable as the tobacco companies, because while paying lip-service to health their true interest is in destroying health so they can manage disease) and living "dangerously" in health and vitality, there is no question in my mind which is the better choice. It is a choice I am happy to reaffirm each day as I mount up and RIDE!!!

untpawgal02 said...

Very interesting stuff! Thanks for sharing!

Gotta Run said...

I only live once... so I am going to be as healthy and toe as many starting lines as I can.

I like you take on the article.

sabina moon said...


Nice article. I think it is useful and unique article. I love this kind of article and this kind of blog. I have enjoyed it very much. Thanks for your website.
How does a triathlon work

sabina moon said...

Nice article. I think it is useful and unique article. I love this kind of article and this kind of blog. I have enjoyed it very much. Thanks for your website.
How does a triathlon work