As a new runner, I am saddened and, honestly, terrified after hearing all the news stories about runners who have died suddenly while running (or after finishing) a race. It's hard not to see these stories and let the very sad outcome of these runners affect your mental strength. As a researcher, I couldn't help but do what I do best.... Google how to stay healthy during marathon training and racing. What I found, might be common sense to most people but to me was new information that is helping me overcome the irrational fear I have developed (don't get me wrong, I am still running races but my head keeps going to the "no no" place of "what if you die while doing this?").
There are a handful of causes of death while running which include sudden death, hyperthermia, hyponatremia, and hypothermia.
Sudden death happens when the body succumbs to the stress of a marathon either from a preexisting condition or the surge of adrenaline. Numerous doctors and exercise experts have dedicated time to research looking at the cardiac problems of runners to address why there seems to be an increase in cardiac related deaths among runners.
Aerobics Center Longitudinal Study found that the most-fit subjects (not super athletes, but those who exercise 15 to 25 miles per week and have a pace that averages 10 mins) are 50% less likely to suffer from heart-disease, as well as less likely to experience a stroke, have diabetes and high blood pressure, are less likely to have cancer, and are at lower risk of showing signs of Alzheimer's. If the ACLS has found that running is very beneficial to our health, what is the cause of sudden death? A runner who is under 35 years old and suffers from a heart attack is more than likely to have a structural defect in their heart (most commonly a misshaped, malfunctioning, enlarged heart - hypertrophic cardiomyopathy). If the runner is over 35, the cause of death is most likely artery disease (cholesterol deposits that rupture and then cause a heart attack) because of the flexing of the the arteries that loosens the deposits and then the cholesterol mixes with the blood forms a clot and then clogs the artery.
Besides preexisting conditions, runners can experience adrenaline surges that can lead to death. The adrenaline surge seems to happen when a runner first sees the finish line. Many times, paramedics are stationed at these areas in races to help runners whom may experience the adrenaline surge. Thankfully the amount of deaths due to adrenaline surges has been on the decrease because of the use of defibrillators. A runner who suffers from an on course heart attack is 50 to 75 percent more likely to be saved, compared to 15 percent on the street.
A runners body temp is controlled by the heart pumping blood to the skin where body heat is lost through sweat. Heat loss can happen through high humidity and dehydration . But hyperthermia can also happen from other circumstances like running a faster-than-usual pace which can cause a high metabolic rate. Runners can also overdress or not remove layers to adjust to the climate. Hyperthermia can also be prevented by drinking the water that is lost from sweat.
The main cause of hyponatremia is drinking too much water, which dilutes sodium levels in the blood causing swelling in the brain. Hyponatremia is much more common in women, slower runners , and those who took over-the-counter nonsteroidal anti-inflammatory drugs. Hyponatremia is most likely to develop after completing a race when sodium is lost in the urine. Staying hydrated by drinking water or sports drinks shouldn't be avoided, because drinking fluids helps maintain adequate blood flow to support demands of running.
Hypothermia is most likely to happen in cold, windy, or wet conditions. Other conditions like running slower during your second half of a race can make it difficult to maintain a proper heat level because sweat is building up and wetting clothes, which cools the body temp especially in cool climates. Besides body temp, hypothermia can also cause serious heart problems.
RECOMMENDATIONS (by International Marathon Medical Director’s Association):
1. Participants should be sufficiently trained and have a corresponding race plan that is appropriate for that level of training and fitness.
2. Have a yearly physical examination being sure to discuss your exercise plans, goals and intensity at that visit.
3. Consume one baby aspirin (81mg) on the morning of a long run/walk of 10k or more is no medical contraindication.
4. Consume less than 200mg caffeine before and during a 10K or more.
5. Only drink a sports drink or its equivalent during a workout of 10k or more.
6. Drink for thirst.
7. Do not consume a NSAID during a run or walk of 10k or more.
8. Consume salt (if no medical contraindication) during a 10k or more.
9. During the last mile, maintain your pace or slow down; do not sprint the last part of the race unless you have practiced this in your training. Run/walk as you train.
After reading all the research and information it has helped me realize the true underlying factors of on course deaths. Death while running is still a scary thought, but the truth is that at some point everyone dies; it's unfortunate but some die while running.
Jane E. Allen (Nov. 21, 2011), Adrenaline-Fueled Sprint Makes Some Marathons Deadly.
Special Report: Are Marathons Dangerous? http://www.runnersworld.com/article/0,7120,s6-238-244--12968-6-1X2X3X4X5-6,00.html
Jake Emmett (2007), The Physiology of Marathon Running: Just What Does Running a Marathon Do to Your Body? http://www.marathonandbeyond.com/choices/emmett.htm
Lewis G. Maharam, Arthur Siegel, Stephen Siegel, Bruce Adams, Pedro Pujol & Paulo Alfonso Lourega de Menezes (March 20, 2010), IMMDA’s Health Recommendations for Runners & Walkers. http://aimsworldrunning.org/articles/IMMDA_Sudden_death_and_how_to_avoid_it_3.20.10.pdf