Dear Dr. B: Physical activity clearly benefits cardiovascular health. But people do die suddenly during or immediately after vigorous exertion like jogging or snow shovelling. What can one do to reduce the risk of sudden death during or after vigorous exertion? Yours: Born to Exercise!
Dear Born to Exercise: This is an interesting question. There are so many benefits to regular physical activity that we tend to forget exercise or any type of physical exertion can kill.
Approximately 6 to 17 percent of all sudden deaths occur in association with exertion and there is evidence to suggest that vigorous exertion simultaneously triggers and protects against sudden death, says an article in the New England Journal of Medicine (NEJM).
The authors of the article looked at the role of vigorous exertion in precipitating or preventing sudden death. It was part of the Physicians Health Study to determine whether vigorous exertion triggers sudden death and whether habitual vigorous exercise diminishes the risk.
About 22,000 male physicians between the ages of 40 to 84 years were studied over a period of 12 years. These physicians were otherwise well and had no obvious cancer or cardiac problems.
The majority of the participants in the study reported exercising vigorously two to four times per week. During the 12-year follow-up, 122 deaths occurred from cardiac causes (in apparently healthy male physicians). Fourteen percent of the deaths occurred during vigorous exertion and five percent of deaths occurred within 30 minutes after vigorous exertion.
These individuals were involved in different types of activities: 68 per cent jogging or racquet sports; 25 per cent other sports; 7 per cent were doing heavy yard work or home repairs.
It was found that the relative risk of sudden death associated with an episode of vigorous exertion was lower among those who exercised more frequently compared to men who rarely engaged in vigorous exercise (less than once a week). Men who exercised at least five times a week had a much lower risk of dying suddenly during or after vigorous exertion.
How can one avoid sudden death from vigorous activity?
There is no good answer to that. The article says that habitually active men have a much lower risk of sudden death in association with vigorous activity. But most active mens risk remained significantly elevated during and after vigorous exertion.
This is scary because is no 100 per cent protection against sudden death. The benefits and risks of vigorous exercise are paradoxical. It is a double-edged sword. The important thing is to know ones limit as regular moderate exercise or physical activity has tremendous benefits. It is an important strategy in the prevention of the cardiovascular diseases and other chronic ailments.
So, if you are Born to Exercise then carry on exercising and stay within your limits. Talk to your family doctor to define these limits. The balance of evidence supports the value and importance of participation in regular exercise regimens, says the NEJM. A good workout is always better than no workout!
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