WASHINGTON — Here’s a message that every one of those derisive “Turning 50?” birthday cards ought to carry: A new study finds that those who are most fit at midlife suffer the fewest chronic diseases after the age of 65 and boost the number of years they will live healthy lives.
It does not, alas, make them live much longer.
Those are the findings of research published Monday in the Archives of Internal Medicine. It’s based on 18,670 men and women who, at around their 50th birthday in 1984, were completely healthy as they underwent a battery of measurements and fitness tests at the Cooper Clinic in Dallas, Texas. After these participants were enrolled at 65 in Medicare, the researchers tracked their health for a 10-year period up to 2010.
They looked for chronic diseases that degrade a person’s quality of life and are costly to treat: ischemic heart disease, congestive heart failure, Type 2 diabetes, chronic obstructive pulmonary disease, chronic kidney disease, Alzheimer’s disease and lung or colon cancer.
They found that physical fitness at midlife made healthy aging a distinct possibility. Those whose fitness levels at around age 50 put them in the top 20 percent of subjects had just over half the number of chronic conditions as did those in the lowest fitness category. And with every step up the fitness ladder at midlife, a participant’s Medicare years were characterized by better health.
In an analysis that looked at 2,406 participants who died during the follow-up period, the researchers found that compared with the most fit at midlife, those who had been least fit spent almost twice as much of their final five years with four or more chronic conditions. Those with the highest midlife fitness levels spent 34 percent more time than the least fit with only one or no chronic disease.
But at every age, the highly fit were not much less likely to die than the less fit, researchers acknowledged. The paper’s authors — a group from the Cooper Institute and the University of Texas’ Southwestern Medical Center in Dallas — said this suggests that midlife fitness “is associated with the compression of morbidity in later life.” For those who were less fit at 50, death may come at the end of a lengthy period of gradual decline; but for the highly fit, it is more likely to come suddenly or at the end of a brief illness, preceded by relative health.
In a commentary published alongside the study, Dr. Diane E. Bild of the National Heart Lung and Blood Institute suggested that the latest research underscores a relatively new possibility for the aging — not that they can prolong their lives indefinitely, but that they can prolong the proportion of their lives lived in relative health.
Tweaking Darwin’s phrase “survival of the fittest,” Bild suggested that those who stay active and exercise at midlife may prove that the fittest thrive instead.