Exercise and the heart — keep it simple

Exercise is a white-hot topic. We must talk more.

This comment on my Facebook page only strengthened my resolve to clarify things.

Not to be flip, snarky (or for that matter even just plain dense) but part of me is asking what’s the point of this? It brings up far more questions than it answers. In the end, we race bikes (with all the attendant risks whatever they may be). What am I supposed to do with _this_?”

I’m here to tell you that exercise is not confusing; it’s easy. You just can’t over-think it.

The too much exercise issue:

The now famous WSJ article, One Running Shoe in the Grave, finally succeeded in shining a light on the concerning observations made in long-time endurance exercisers. The brouhaha that emerged has been striking. Endurance exercisers, who know inflammation all too well, reacted defensively. Couch potatoes said, see…we told you so. Major media ran irresponsible headlines suggesting that running may be harmful to your heart. I hated that headline. Goofy sensationalism works against those of us who are trying.

I’m often asked why I write about the endurance exercise/heart-scar topic; what’s my agenda? Here is the comment I left on the WSJ article:

“As a heart rhythm doctor and a bike racer, the steady stream of seemingly super-healthy endurance athletes that populate my practice piques my interest. Why is it that someone so fit and so strong could develop the same diseases that sedentary overweight smokers get? Why is that heart CT scans of marathon runners look like those of smokers? Why is that Born-to-Run types suffer sudden death unexpectedly early? How do we ignore the multitude of studies on long-term endurance exercisers that show (otherwise unexpected) cardiac scars? It’s well known that scar in the heart predisposes to electrical abnormalities.

Here’s the problem for cardiologists: the overwhelming majority of the disease we see occurs in large part because of inadequate exercise. Most should exercise more. But like everything in life, too much of something is….well…too much.”

Let’s be clear about what this “new” data means: it suggests the possibility that those who exercise excessively over long periods of time may be putting themselves at risk for heart disease. This shouldn’t be controversial. It should be interesting and deserving of more investigation. Writing on his site, The Athlete’s Heart Blog, heart surgeon and triathlete, Larry Creswell said it well: “We need to keep an open mind as we continue to learn about the long-term cardiac consequences of endurance sport.” (If you haven’t already, you should read and Evernote this incredibly thorough and well-written post.)

This leads to the next question: How much exercise is too much?  I’m sorry. The answer is not knowable. That’s because humans are different. One person’s 8-minute mile is another’s 6-min mile. One person’s hour-long ride covers 25.4 miles, while another goes only 10 miles. Then there is genetics. Clearly there are varying degrees of susceptibility.

Back to my FB friend who asked about the point of all this…

Here it is friend: These revelations do not argue against exercise. They should inform patients and doctors of a POSSIBLE danger. Surely, the chance of ossifying (turn to bone) heart arteries or replacing heart muscle with scar warrants attention.

Humans aren’t newts. We have only one heart–that does not repair itself. Cell biologists remain a long way from gifting us the ultimate mulligan—stem cells.

Would being diagnosed with these afflictions cause you to make choices?

Long-time bike racer Steve Tilford answered this question well: (emphasis mine)

I am a bike racer. That is pretty much what I’ve done my whole life. It doesn’t necessarily define me, but it has molded me into who I am. I don’t plan on giving up this sport for anything. But, if someone could convince me that I might be in imminent danger, health-wise, if I keep competing, then I’d have to rethink the whole thing. I love the lifestyle, but without being alive you can’t have it either.

JMM