A veteran distance runner, seemingly in top shape, collapsed during the White Rock Marathon on December 14, 2008 in Dallas, TX on and later died in the hospital. There was no immediate determination of the cause of her collapse. Erin Lahr, a 29-year-old newlywed from Austin, TX, might have succumbed to the heat and dehydration, as strong winds and a fast 20-degree climb in temperature affected other runners.
Because there have been deaths during other marathons over recent years, the question arises: why do marathoners die?
Most of the victims had pre-existing heart conditions. One man who died during the 2007 Chicago Marathon had a heart condition that was ruled the cause of death, not the record high heat and humidity.
Hyponatremia, or extremely low sodium in the blood, was the cause of death for a woman running the 2002 Boston Marathon. She was drinking only water and not replacing electrolytes lost while running.
Heat exhaustion and heat stroke have also been the reason for runners being sent to the hospital after even a short distance event. Endurance athletes put themselves at higher risk deaths among marathon runners is relatively rare. Nonetheless, death among distance runners is rare.
The bottom line is that, even if you're not a runner or elite endurance athlete, listen to your body, and be well-trained and prepared going into a demanding activity.