Exercise and Cardiovascular Aging
As a companion piece to a recent paper on the degree to which cardiovascular aging can be postponed through lifestyle choices, here researchers review the differences observed in the cardiovascular system between people who do maintain physical activity and people who do not. While the benefits are undeniable, you can't reliably exercise your way to living to 100 in good health - the majority of physically fit people don't make it to 90 given today's level of medical technology, and everyone who lives to 100 is greatly impacted by the damage of aging. However, the fact that we live in an era of accelerating progress in biotechnology and its application to medicine suggests that every extra year counts. The technologies of tomorrow will be far more impressive than those of today. That extra year might mean that you avoid dying too early, or being too frail to benefit from the first generation of rejuvenation therapies that will emerge over the next few decades.
Chronological age is identified as the major risk factor for cardiovascular morbidity and mortality, with older people significantly more likely to have cardiovascular disease. In the absence of hypertension or clinically apparent cardiovascular disease, the cardiovascular system undergoes structural and functional changes with age that compromise cardiac reserve. These age-associated cardiovascular changes lower the threshold for the three major cardiac pathophysiological conditions such as left ventricular hypertrophy, chronic heart failure and atrial fibrillation, all seen with increasing age.
In order to understand the effects of aging on the cardiovascular system, it is important to consider the complex interaction between the heart as a pump and the afterload on the heart imposed by the arterial system. Cardiac aging is associated with progressive loss of myocytes and compensating mild hypertrophy, but also with reduced sensitivity to sympathetic stimuli that compromises myocardial contractility and pumping ability in older people. With advanced aging, the large arteries dilate, their walls become thicker and stiffer due to collagen and calcium deposition and fragmentation of the elastic fibres.
Physical activity, exercise, and associated high level of cardiorespiratory fitness reduce all cause and cardiovascular mortality, the risk of heart failure and myocardial infarction, and age-related arterial and cardiac stiffening. Epidemiologic studies investigating the association of physical activity with cardiovascular disease risk have been conducted for more than six decades now. The earliest studies from the 1950s showed that men who were physically active on the job experienced coronary heart disease mortality rates that were approximately half those of men who were sedentary at work. Following these observations, studies in the 1960s showed that men who died from coronary heart disease were approximately 40% to 50% less likely to be recreationally active, compared with men who remained alive.
Numerous epidemiological studies were published since these early investigations reporting strong association between physical activity in cardiovascular health with 30% to 40% reduction in all-cause and cardiovascular mortality in active men and women of different age. Conversely, low active and sedentary behaviour are associated with 63% greater risk to develop cardiovascular disease. From the evidence available it is now clear that physical activity and exercise can attenuate the age-related cardiovascular changes by improving functional capacity of the cardiovascular system, cardiac function, and metabolism.