Exercising on the Edge

A couple weeks ago a strange and terrible thing happened: three runners died in the Detroit Half Marathon. The men, 26, 36, and 65, all died within sixteen minutes of each other. News of the tragedy gave pause (hopefully a short one) to endurance athletes everywhere.

In wake of the tragedy, the Internet buzzed with speculation as to what happened. One blogger was convinced that a demented person had poisoned the water at one of the rest stops. It will be interesting to see what the pathologists conclude, if made public.

Facts regarding each of the men's health and medical history are few. They were probably in pretty good shape based on what I've read. The death of the 65 year old was no great a surprise because, as every TOJ knows, odds of sudden death during exercise rise steadily as a function of age, and he reputedly had some lung problems. When young men die during exercise, it is usually attributed to an electrical conduction or other hidden heart defect.

The weekend after the Detroit event I received an email from Dr. Al Sears (http://www.alsearsmd.com/), who runs a wellness and longevity center in Florida, and is a strong opponent of aerobic training, especially running marathons. His email claims this type of exercise "shrinks your lungs and downsizes your heart's output." Further, studies have shown that blood samples taken from people who have completed marathons have exhibited the same enzymes that are present during a heart attack. Dr. Sears sells an program that is based on progressively short anaerobic bursts of exercise, which be believes are safer and help you live longer.

I forwarded his email to another TOJ who is a distance runner (had just finished the Humboldt County Marathon in California) and a physician. His reaction was illuminating. He said it might be true you live longer if you exclusively follow a short interval program like Dr. Sears, but there is no scientific evidence that it does. Furthermore, most distance runners use a variety of exercise, including intense progressive intervals.

This distance runner/physician's most important point was that how you exercise really depends on the outcome you seek. If you want to run a marathon, you have to train for it, which is true for any challenging physical endeavor. If your goal is just to live a long time, it might not be necessary to do many of the forms of physical exercise that a TOJ enjoys. Most TOJs exercise hard because it enhances the quality of their lives. Quantity, as measured in years, is just a secondary effect, and subject many other factors like genetics and environment.

My friend speculated that there might be subsets of people for whom distance running is good, and others for whom it is detrimental. But being able to identity who falls into which category waits future study. Right now, to use his words, we are still in the medical dark ages when it comes to long term effects of exercise.

For most of us, any exercise where you ramp up your heart rate -- whether in intense, sub-minute anaerobic bursts that leave leave you breathless or in long aerobic activities where you dwell minutes and hours at at the burning upper end of your aerobic capacity -- presents some risk. You don't know know where you reach a dangerous tipping point, and, luckily most of us never find out.

The men whose lives ended in Detroit did. While it is doubtless a tragedy for their family and friends, this TOJ admires that they were in the race.

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