Dr. Maharam: I have noticed that most half-marathon and marathon deaths seem to be happening before the finish. I understand there is discussion about research on this but do you have any thoughts as to why runners are collapsing at this specific spot? – LeeAnn, Wheeling, W. V.
LeeAnn: I am so glad you asked. We at the International Marathon Medical Directors Association have been discussing this. Given the recent death at the LA Rock n Roll Half Marathon last weekend, I now get a chance to explain what medical directors are doing. The race course is really the safest place to be on a race day unless you are standing in the middle of an Emergency Room. We are all stationing paramedic units at that very spot – what we call the “X-Spot” where runners first see the finish line and know they are going to finish.
The prevailing theory about sudden death (fatal cardiac arrhythmia) in healthy patients in an endurance event, as we have discussed here before, is that either a caffeine load of more than 200 mg has caused enough decreased blood flow to disrupt an ischemic area’s electrical rhythm, or the release of muscle byproducts has caused a small plaque to activate platelets and a small clot to form in a coronary artery. Either of these things can cause a fatal arrhythmia. Limiting caffeine and taking a baby aspirin should help eliminate these possibilities.
The X-spot is where a runner knows he (or she) is going to finish the race, or where he can see the finish line and push to a hard sprint finish. This adrenaline rush, we think, might push the electrical system of the heart to an arrhythmia if the muscle is ischemic by one of the two mechanisms described above or if the participant has underlying heart disease. Not pushing yourself that last mile and taking it as you have the last few miles might make participating safer. So would encouraging announcers not to goad runners by saying things like, “If you can hear my voice you can break 4 hours!”
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