Here is a link to summary of the paper by Dr. Paul Bhella et al. entitled "Impact of Lifelong Exercise "dose" on Left Ventricular Compliance and Distensibility"
Here is the authors'conclusion :
" Low doses of casual, lifelong exercise do not prevent the decreased compliance and distensibility observed with healthy, sedentary aging. In contrast, 4 to 5 exercise sessions/week throughout adulthood prevent most of these age-related changes. As LV stiffening has been implicated in the pathophysiology of many cardiovascular conditions affecting the elderly, this "dose" of exercise training may have important implications for prevention of cardiovascular disease."
Is there an age related decrease in left ventricular compliance. According to a 1984 article by Rodeheffet et al the aging heart may be able to maintain cardiac output in the face of an age associated decrease in maximal heart rate by increasing stroke volume. See here for link. The older person relies more on an increase in end diastolic volume and riding the beneficial part of the Starling curve, but if the left ventricle become less compliant, which it is claimed it does as a function of age that adaptation would only work for a while.
Is the decrease in LV compliance due to just getting old or might it be due to lack of vigorous physical exercise. Dr. Armin-Zaeh and coworkers at the Dallas Based Institute for exercise and environment medicine believe it is the latter. See here. My personal bias is obviously to agree with them. Here are the conclusions from the above linked article.
"In conclusion, a sedentary lifestyle
is associated with a decline of ventricular compliance, leading to
higher cardiac filling
pressures and lower stroke volumes for a given
filling volume compared with age-matched athletes or young individuals.
Prolonged,
sustained endurance training preserves
ventricular compliance with aging and may be an important approach to
reduce the probability
of heart failure with aging."
A partial,apparent counterpoint to the above studies can be found here in this 2003 article by P E Gates and co-authors whose analysis and summary minimized the importance of one of their own findings ( namely that a standard measure of diastolic function (the e/a ratio) was higher in endurance trained subjects) and instead emphasized the value of the decreased arterial stiffness noted in long term exercisers.Either way, a less stiff ventricle and/or a less stiff aorta, it is good news to long term endurance exercisers.
addendum: 10/1/14 Correction made on title, "Stiffness" changed to "Compliance"
addendum-1/22/14 Title reworded to a less awkward version
A partial,apparent counterpoint to the above studies can be found here in this 2003 article by P E Gates and co-authors whose analysis and summary minimized the importance of one of their own findings ( namely that a standard measure of diastolic function (the e/a ratio) was higher in endurance trained subjects) and instead emphasized the value of the decreased arterial stiffness noted in long term exercisers.Either way, a less stiff ventricle and/or a less stiff aorta, it is good news to long term endurance exercisers.
addendum: 10/1/14 Correction made on title, "Stiffness" changed to "Compliance"
addendum-1/22/14 Title reworded to a less awkward version
1 comment:
I guess it would dear doc. Well, as we grow old, there are so many changes in our body and we need to do an exercise as much as possible. You are a retired doctor and I do believe that you have so many experiences in your career.
John Doe
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