Exercise and Life Expectancy of the Heart -- A Thought Provoking Conundrum

When will your heart die?  When will it stop beating?  Does a heart have a predestined number of beats and then thats it?  If so, does exercise increase that limit, or does it merely use up the beats more quickly thereby reducing the lifespan of the heart?  Are you actually shortening your life by racing your heartbeat during exercise day after day? 

Most studies have supported that exercise can extend your life when compared to a sedentary lifestyle, however the thought of your heart only having a certain number of beats in it is interesting.
 enough to maintain the average 72 bpm for 80 years your heart will beat 3,027,456,000 during your lifespan.72 x 60 x 24 x 365 x 80
bpm x min x hr x days x year

If you are healthy

But what if that 3,027,456,000 is a preset threshold and you reach it more rapidly because of elevated heart rates due to exercise?  Or what if the genetics of your heart tissue at the cellular level predetermine how many times your heart will beat in a lifetime?

It's an interesting conundrum isn't it. 

I am not an overly religious person, but I consider myself spiritual.  To that end, I believe that your life, not your heart; has a preset expiration date in which you are given some ability to influence.  Making healthy decisions "most" of the time I think would extend that expiration date.  Mostly I think the quality and meaning of your life is more important than how long it is.  Abraham Lincoln said it best:  "and in the end, it's not the years in your life that count.  It's the life in your years."

Food for thought:

Studies have shown that the average elite athlete will die by the age of 67. That is considerably lower then the 76 year life expectancy of the average American. According to the NFL Players Association, the average life expectancy of an NFL player is 58 years of age.

The Framingham Study  A survey of the effects of exercise on mortality in 1,404 women, aged 50-to-74, in the famous Framingham study was reported in the American Heart Journal in Nov 1994. The scientists found that after 16 years of follow-up, 319 (23%) of the women had died, but that the mortality rate was lowest in women who had exercised most vigorously. They found that this increase in longevity was not due to reduced cardiovascular mortality.

The Harvard Alumni Health Study One of the most comprehensive studies to look at how exercise affects life expectancy is the Harvard Alumni Health Study, which was started in 1962 with 16,936 male Harvard alumni aged 35-to-74, under the direction of Stanford University epidemiologist R.S. Paffenbarger, Jr.. A series of reports on the findings of this study have been published in medical journals since 1986 when the New England Journal of Medicine carried a report entitled "Physical activity, all cause mortality, and longevity of college alumni".  In that report the scientists said they had obtained data over a 12-16-year period (1962-1978) about the extent and kind of exercise engaged by the Harvard alumni including activities such as walking, stair climbing, and sports such as swimming, tennis, basket ball, and golf. They found that 1,413 of the study subjects died during this period and that mortality rates (primarily from cardiovascular and respiratory causes) declined as physical activity increased, with mortality rates being "one quarter to one third lower among alumni expending 2,000 or more kcal during exercise per week than among less active men."

Dr. Kim Chong-in of Wongwang University conducted a lifespan survey using newspaper obituaries of for some 2,100 people between 1963 and 2000.  He discovered that athletes ranked 9 out of 11 for life span.  http://home.donga.ac.kr/~daudh/magazine/118/bitter.htm

And how about these studies to further ponder the mysteries of the heart? 

http://www.fiercebiotech.com/press-releases/new-method-regenerating-heart-muscle-direct-reprogramming

http://www.brown.edu/Courses/BI0032/adltstem/ct.htm

http://singularityhub.com/2009/11/03/harvard-grows-heart-tissue-watches-it-beat/


0 comments:

Post a Comment