I've written previously about the rate of SCA at long-distance running events. We learned from a careful study (of nearly 11 million runners) reported earlier this year [1] that the rate of SCA is approximately 1 per 100,000 marathon participants and approximately 1 per 300,000 half marathon participants. The mean age of victims was 42 years and 86% were men. For the non-surviving victims in whom autopsy information was available, the vast majority had an underlying heart condition such as hypertrophic cardiomyopathy (HCM), other abnormal hypertrophy, heart valve disease, or coronary artery disease.
Interestingly, the occurrences of SCA were not distributed uniformly along the length of the race. In marathons, the SCA events were much more common in the 20 mile-to-finish segment. Similarly, in half marathons, the SCA events were much more common in the 10 mile-to-fiinish segment. One reasonable hypothesis is that the SCA events in the final miles of the races may be linked to an increase in adrenaline levels as runners lift the pace or surge toward the finish line.
Today, I thought I'd share some recommendations from the International Marathon Medical Director's Association (IMMDA) that were approved in March, 2010 and address the issue of how athlete's can best prepare and execute a long-distance running race with an eye toward preventing SCA. You can review the original report to review the rationale, but I'll summarize the important recommendations here:
1. Participants should be well-trained and have a race plan that matches their 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 a baby aspirin (81 mg) on the morning of the race if there is no contraindication to do so. I'd recommend discussing this with your doctor beforehand.
4. Consume less than 200 mg of caffeine before/during a 10K or longer race.
5. Only drink sports drink (or equivalent) in races of 10K+.
6. Drink for thirst.
7. Do not consume NSAIDS (eg, Motrin, ibuprofen) during a race of 10K+.
8. Consume salt (if no medical contraindication) during a 10K+ race.
9. During the last mile, maintain your pace or slow down; do not sprint the last part of the race unless you have practices this in your training.
These are very thoughtful recommendations. The chances of any single athlete suffering race-related sudden cardiac death is small, but athletes should do the reasonable things to help prevent this type of tragedy.
[1] Kim JH, et al. Cardiac arrest during long-distance running races. NEJM 2012;366:130-140.