Friday, November 5, 2010

Lab tests are not all the same

TIME Healthland posted an article on Oct 25 regurgitating the results of yet another study which "discovered" that after marathons, the same lab test that goes up in a heart attack (troponin) goes up after running 26.2. While I am sure the scientists reporting the study results did a fine job, the reporting could use some work. First, there are literally dozens of studies that have already shown this. Second, no one that I am aware of has shown that the increased troponin in marathon runners means a damn thing. For example, if your troponin goes up after a marathon, are you going to die sooner? Have a heart attack or suddenly die during a race? Those are the important things, not that your lab test is abnormal.

Lots of things can make your troponin go up, like getting in a car wreck and crushing your chest against the steering wheel. Or getting an infection on your heart valves. Or having a viral infection. Why aren't we comparing marathon running to these things? There is a lab test called the GGT. It is a marker of liver function. If you go out on a bender and have a half a bottle of tequila, your GGT will go up. Your GGT will also go up if you catch hepatitis, or have liver flukes, or eat magic mushrooms, or OD on acetaminophen. Now, is anyone out there saying that drinking tequila is the same as all these things?

It is certainly possible that endurance sports are doing something unsavory to the cardiovascular system, but at the present time, I am not aware of any such evidence and until you have something convincing, I wish the media would stop trying to scare people away from running, when all the available evidence points to it being healthy!


  1. Dr. Dave - I fully agree, and share your view that the media seems inappropriately intent on scaring people away from running. Worse, they want to lead people to the false conclusion that exercise will not help them lose weight (see Dr. Monty's excellent response to Time here: Seems like there's a good RRT discussion on-topic, and Dr. Monte would probably be agreeable to join a like-minded M.D. since he was co-host on the original RRT-001 (he can be reached at