By Jonny Lupsha, Current Events Writer
New research seems to confirm that truly stopping the aging process is a myth. Although human life expectancy increases as we conquer diseases, our bodies do inevitably age. We can, however, truly make the most of it.
For decades, the beauty industry has attempted to unlock the secrets of stopping or reversing the aging process. The subject has even found its way into science fiction and horror. Now, a study published in the scientific journal Nature found reason to support a line of thinking known as the “invariant rate of aging” hypothesis, which states that the rate of aging is “relatively fixed within species” due to “biological constraints.”
However, the inevitability of aging is not the portent of doom often portrayed in magazine ads and movies. In her video series How to Stay Fit as You Age, fitness and wellness consultant Dr. Kimberlee Bethany Bonura explained the physiological changes of aging and what they do—and don’t—mean for our lives.
First, the Bad News
According to Dr. Bethany Bonura, even in the absence of disease, a certain degree of structural and functional deterioration happens in the majority of physiological systems as we get older, including our bodies’ organ systems and tissues. Understanding them can help us ease our concerns about aging.
“Physiological aging includes declines in maximal aerobic capacity and skeletal muscle performance,” she said. “What that means is that a fit man of 25 will run faster than a fit man of 65, but—across the range of capacity—we determine where we are, with our own levels of activity and exercise.”
In other words, a 22-year-old man who’s in excellent physical condition has a higher aerobic capacity and muscle capacity than a 66-year-old man in the same condition, but the same 66-year-old man is more capable and fit than a 22-year-old who doesn’t take care of himself.
“Another aspect of physiological aging is changes in body composition,” Dr. Bethany Bonura said. “Between the ages of 18 and 55 years, the average sedentary American will gain between 17 to 20 pounds of fat; between 55 and 65, we will gain another two to five pounds of fat. There is also a loss of muscle, called sarcopenia, during middle and older age.”
From there, she said, it’s a domino effect. As we gain weight and lose muscle, our metabolism slows, which causes us to gain more weight. To a degree, these changes inevitably occur due to age-related differences in hormone production.
Now, the Good News
According to Dr. Bethany Bonura, this cascade of degeneration isn’t inevitable—or at least, not as much as the aging process itself seems to be. At any age, including seniors over age 75, changes in diet and exercise lead to considerable results.
“One study with frail, institutionalized adults over the age of 90 found that just eight weeks of resistance training led to strength gains of 174%, and increased their walking speeds by 48%,” she said.
It isn’t just resistance training in nonagenarians that can help. Comparing older athletes to age-matched peers paints a broader, brighter picture of the physiological and health benefits that active seniors can reap.
“They have a more favorable body composition profile, with less total body fat and less abdominal fat; they have greater muscle mass and higher bone mineral density,” she said. “They are also 30% to 50% stronger than their sedentary peers are. They have improved aerobic fitness, including more oxidative and fatigue-resistant limb muscles, a higher capacity to transport and use oxygen, a higher cardiac stroke volume at peak exertion, and a younger pattern of left ventricular filling.”
All this means that athletic seniors are more capable of aerobic exercise like walking, biking, and swimming for longer periods of time than seniors who aren’t athletic—and they can do so with less fatigue.
Aging may be inevitable, but minimizing the declines that come with it remain in the control of the individual.